Active vs. Passive Voice

For a long time scientists wrote in the passive voice when publishing their work in peer-reviewed journals or when writing in other forms, but they now prefer to write in the active voice in most situations1, 2, 3.

Generally, writing in the active voice should enhance conciseness and clarity4. For this reason, we believe that teaching science students to use the active voice (in most scenarios) will improve their writing. Our resources on this writing skill will help students learn the difference between the active and passive voice, spot the occasions when it might be preferable to use the passive voice, and then test their application of these concepts.

Lesson and Workshops Introduction:

We have designed pre- and post-class activities (essentially ‘homework’ exercises for students) to complement the in-class lesson/workshop for this specific science writing-skill component (‘Active vs. Passive Voice’).

At our institution, we ask students to complete the pre-class activities online as preparation for the in-class lesson/workshop, so as to give them some exposure to the concepts that will be explored in more detail in class.

The in-class activities are designed to improve students’ writing skills and to give them experience in working with partners/small groups on related activities. The in-class lesson/workshop has been designed to encourage an interactive, conversational approach to completing the activities; this should help students to resolve any confusion from the pre-class activities and discuss the importance of the writing skills they are learning to master with their peers and instructors. We provide student worksheets for the in-class activities, as well as TA and Instructor versions of these worksheets, which also include suggested solutions to the activities. We also provide a PowerPoint presentation to accompany the lesson/workshop, and a timing guide with teaching prompts to help instructors encourage students to get the most from these sessions.

Lastly, students are asked to complete the post-class activities online, as a final learning tool and wrap-up to help them solidify the concepts they have learned and gain some more practice in applying these to real writing situations.


A Note on Asking Students to Complete the Pre- and Post-Class Activities Online

We recommend asking students to complete the activities online so as to reduce the likelihood that worksheets of these activities are printed and enter the student domain; over time, these questions will reduce in value if copies are posted online (via blogs etc. by students who have previously completed them).

We have designed these activities to take students approximately 30-60 minutes to complete; they form a small part of the graded continuous assessment for students enrolled in a science communication course at our institution, but could also be deployed as not-for-credit activities.


A Note on the Different Versions

All different versions/banks have been used and refined following student and instructor feedback, and all of them focus on the same important concepts. We cycle different versions across different terms to minimize the potential that students enrolled in our course in concurrent terms will share answers (e.g. we do not use the same version in concurrent terms).

Please note that while the initial choice of which version to use is somewhat arbitrary, it is important to use the same version for the pre-, in- and post-class activities as a whole unit; this is because some of the questions appearing in the in-class lesson/workshop and/or post-class activities build on work completed in the pre-class activities (e.g. do not use pre-class version 1, and post-class version 2 together).

 

Version 1

Active and Passive Voice: Student Pre-Class Activities

Many people are confused by whether they are using the active or passive voice when writing, and in which scenario each is preferred. Thankfully, there is a simple way of identifying the two styles; the key to understanding the difference between them is to spot the subject and the object in each sentence, and then selectively order the way you introduce them.

In an active sentence, the subject is the element that is doing the action, whereas the object is the element that is receiving the action. In contrast, in a passive sentence, the element targeted by the action is promoted to the subject position. This can sound confusing, but a good way to learn this concept is to realize that a passive sentence will result in the subject effectively doing nothing, because whatever is happening is being done to it.

Some examples

1A:Consider the following active voice sentence:

I weighed the fish on weighing scales every week.

‘I’ is the subject here, because ‘I’ did the action (weighing) reported in this sentence, whereas the fish is the object because it is receiving the action (being weighed). It cannot be a passive sentence because the subject is doing something to the object (weighing it).

1P: Now, consider the passive voice version of the previous sentence:

The fish was weighed by me on weighing scales every week.

The fish is the subject here because it is the focus of the sentence, but you know this cannot possibly be an active sentence because the subject is effectively doing nothing; the ‘me’ is the part of the sentence doing the action (weighing).

2A: Consider the following active voice sentence:

More than 50,000 students applied to Oxford University last year.

‘More than 50,000 students’ is the sentence subject here, because these students were the ones doing the action (applying), whereas ‘Oxford University’ is the object because it is receiving the action (the applications). It cannot be a passive sentence because the subjects are doing something (applying) to the object.

2P: Now, consider the passive voice version of the previous sentence:

Oxford University was applied to by more than 50,000 students last year.

‘Oxford University’ is the subject of the sentence here, but you know the sentence must be passive because the subject is effectively doing nothing; the ‘more than 50,000 students’ are the ones doing the action (applying).

Why does this matter?

In the examples listed above, the passive versions are not especially long-winded, yet if you re-examine them you will notice that they feature more words than their respective active versions. This is of great relevance to you as science writers because it is very important that you always try to communicate things as concisely as possible. When you start to write more complex sentences, the difference in word count can be significant when you compare the active and passive versions, and this is important in a setting in which waffly, vague statements are always your enemy.

Along with a lack of conciseness, ambiguity (being vague) is the other unwanted attribute that comes with the use of passive voice sentences. For example, consider the following active and passive versions of a sentence that might appear in the Methods section of your lab report:

3A: Professor Roberts kept the mice in their cages for three weeks. He then released them into the wild and recaptured them three weeks later.

3P: The mice used in this experiment were kept in their cages for three weeks before they were released and then recaptured after they had spent three weeks in the wild.

Note firstly that the active version features 24 words in comparison to the 30 in the passive one, yet, importantly, the active version explains exactly what happened and who did what, whereas the passive one leaves these specific details out.

Question 1 (6 marks)

Are the following sentences written in the active or passive voice? Copy and paste the whole set of six sentences and then answer either 'active' or 'passive' for each one.

Sentence 1: Difficulty differentiating between active and passive voice is frequently experienced by students at UBC.
Sentence 2: The importance of learning these differences is known by writers and presenters.
Sentence 3: In general, communicators prefer to use the active voice.
Sentence 4: Thoughts are usually expressed more concisely by speakers and writers in this way.
Sentence 5: However, in certain situations, it is more advantageous for the passive voice to be used by the author.
Sentence 6: Instructors (and these guides) will highlight some of these examples later in the course.

Questions 2, 3, 4, 5 (2 marks each, 8 marks total)

For questions 2 - 5, you need to read each sentence and decide (1 mark) whether it is:

(a)Written in the active voice, or
(b)Written in the passive voice

Once you have decided this, you need to re-write the sentence so it is in the other style of voice (1 mark). For example, if the original sentence is written in the passive voice, re-write the sentence in the active voice. Hint: The goal of this activity is to demonstrate that you are able to distinguish between the active and passive voices when writing. In some cases, you would not want the sentence to be in the other style of voice; however, being able to re-write a sentence from active to passive, or vice versa, is a useful skill to practice.

Question 2 (2 marks)

A new tree frog species was discovered by scientists on a three-week expedition in a South American rainforest.

Question 3 (2 marks)

Due to the frog’s chocolate-coloured skin, researchers named it the cocoa frog.

Question 4 (2 marks)

In order to climb trees, this frog uses round discs located on its fingers and toes.

Question 5 (2 marks)

A total of 60 new species, including 11 fish, one snake, and five other frogs were discovered by the scientists while on their expedition.

Questions 6 and 7 (3 marks each, 6 marks total)

For questions 6 and 7 you need to read each sentence and decide (1 mark) whether it is:

(a)Written in the active voice
(b)Written in the passive voice
(c)Written in the active, then passive voice
(d)Written in the passive, then active voice

Once you have decided this, re-write the sentence so it is in the other voice (2 marks).

For example, if the original sentence is written in the passive voice, re-write the sentence in the active voice. Hint: If you answer either (c) or (d), your re-written sentence will require two changes.

Question 6 (3 marks)

The researchers also tested water quality in the area, while plant and animal species were surveyed by specialists on the team.

Question 7 (3 marks)

Worryingly high concentrations of mercury were found in the river system by the researchers, who thought it might have come from illegal mining work in the rainforest.

Question 8 (2 or 4 marks each, 10 marks total)

Depending on whether your sentence is written in the active or passive voice, the form of the verb will often be different. Active voice sentences are typically associated with ‘strong verbs’ that explain what the subject is doing to the object in the sentence. The exercise below is designed to make you aware of this other subtle difference between the active and passive voices.

Fill in the blanks in the following sentences with the correct form of the verb attached to each topic:

A: Topic = evolution, verb = to favour (2 marks)

Active: Natural selection [?????] organisms best adapted to their current environment.
Passive: Organisms best adapted to their current environment are [?????] by natural selection.

B: Topic = recycling, verb = to reduce (2 marks)

Active: We can [?????]landfill waste by recycling cardboard and plastic containers.
Passive: Landfill waste can be [?????]by the recycling of cardboard and plastic containers.

C: Topic = vaccinations, verb = to protect (2 marks)

Active: The bestvaccine is one that [?????] individuals against a disease by stimulating the immune system without causing too much of a reaction.
Passive: Individuals can be [?????] against certain diseases by vaccines that stimulate the immune system without causing disease.

D. Topic = flamingos building nests, verb = to begin; to lay (4 marks)

Active: Up to six weeks before the female flamingo [?????] her eggs, male and female flamingos will [?????] to build nests.
Passive: The process of nest building is [?????] by flamingos gathering mud, stones, and small sticks, up to six weeks prior to eggs being [?????].

Version 2

Active and Passive Voice: Student Pre-Class Activities

Many people are confused by whether they are using the active or passive voice when writing, and in which scenario each is preferred. Thankfully, there is a simple way of identifying the two styles; the key to understanding the difference between them is to spot the subject and the object in each sentence, and then selectively order the way you introduce them.

In an active sentence, the subject is the focus of the sentence (the element that is doing the action), whereas the object is the element that is receiving the action. In contrast, in a passive sentence, the element targeted by the action is promoted to the subject position and becomes the focus of the sentence. This can sound confusing, but a good way to learn this concept is to realize that a passive sentence will result in the subject effectively doing nothing, because whatever is happening is being done to it.

Many people confuse ‘voice’ with ‘tense’ and it is important that you learn they are two very different things; both active and passive voice sentences can be written in any tense (present, past, future etc.).

Some examples

1A: Consider the following active voice sentence:

Phil weighed the mice on weighing scales every week.

‘Phil’ is the subject here, because ‘Phil’ is the person doing the action (weighing) reported in this sentence, whereas the mice are the objects, because they are receiving the action (being weighed). It cannot be a passive sentence because the subject is doing something to the object (weighing it).

1P: Now, consider the passive voice version of the previous sentence:

The mice were weighed by Phil on weighing scales every week.

The mice have become the subject here because they have been promoted to the focus of the sentence. This cannot possibly be an active sentence because the subject is effectively doing nothing, whereas in the active version (1A). the subject actually did something (the weighing).

2A: Consider the following active voice sentence:

More than 50,000 students applied to <snap style="color:blue">Oxford University last year.

‘More than 50,000 students’ is the sentence subject here, because these students are the focus of the sentence (and doing the applying), whereas ‘Oxford University’ is the object because it is receiving the action (the applications). It cannot be a passive sentence because the subjects are doing something (applying) to the object.

2P: Now, consider the passive voice version of the previous sentence:

Oxford University was applied to by more than 50,000 students last year.

‘Oxford University’ is the subject of the sentence here, but you know the sentence must be passive because the subject is effectively doing nothing; the ‘more than 50,000 students’ are the ones doing the action (applying).

Note: Another trick that can often highlight sentences written in the passive voice is to look for the verb ‘to be’. For example: “The exam was administered by the teacher,” and “The matches were played by the teams” are both passive voice sentences, whereas “The teacher administered the exam,” and “The teams played the matches” are the active versions.

However, there are pitfalls to this, which is why it is better to learn this concept as set out initially. For example: “Professor Canuck wants to be recognized as the leading researcher in his field,” is an active sentence but still includes ‘to be’. It is active because the subject is performing the action (the wanting) on the object.

Why does this matter?

In the examples listed above, the passive versions are not especially long-winded, yet if you re-examine them you will notice that they feature more words than their respective active versions. This is of great relevance to you as a science writer because it is very important that you always try to communicate things as concisely as possible. When you start to write more complex sentences, the difference in word count can be large when you compare the active and passive versions, and this is important in a setting in which waffly, vague statements are always your enemy.

Along with a lack of conciseness, ambiguity (being vague) is the other unwanted attribute that comes with the use of passive voice sentences. For example, consider the following active and passive versions of a sentence that might appear in the Methods section of your lab report:

3A: Professor Roberts kept the mice in their cages for three weeks. He then released them into the wild and recaptured them three weeks later.

3P: The mice used in this experiment were kept in their cages for three weeks before they were released and then recaptured after they had spent three weeks in the wild.

Note firstly that the active version features 24 words in comparison to the 30 in the passive one, yet, importantly, the active version explains exactly what happened and who did what, whereas the passive one leaves these specific details out.

Questions 1, 2, 3, 4 and 5 (1 mark each, 5 marks total)

For questions 1, 2, 3, 4 and 5 you should read each sentence and decide whether it is written in the active voice (or not).

Question 1 (1 mark)

The scientists were embarrassed by a mistake that appeared in their journal article.

Question 2 (1 mark)

The scientists realized that they needed to state their argument more clearly when they saw it in the journal.

Question 3 (1 mark)

According to one reviewer, an ethics protocol had also been violated by them.

Question 4 (1 mark)

On a more positive note, the researchers improved their writing skills considerably when they first prepared the article.

Question 5 (1 mark)

It had been thought by some of them that science was just about working in a laboratory until time was spent watching monkeys in the jungle.

Questions 6, 7, 8 (1 mark each, 3 marks total), 9 and 10 (2 marks each, 4 marks total)

For questions 6, 7, 8, 9 and 10, you need to read the passive voice versions of different sentences and then re-write them in the active voice. Questions worth two marks require two changes (from passive to active).

Question 6 (1 mark)

Passive Version: Very little is known by us about the eating habits of the snow leopard.

Question 7 (1 mark)

Passive Version: Over the last 20 years, there has been an enhanced effort made by conservationists to educate the public about the importance of preserving leopard habitat.

Question 8 (1 mark)

Passive Version: But have we been persuaded by researchers that habitat loss is to blame for snow leopards becoming rarer?

Question 9 (2 marks)

Passive Version: The exam booklets were carefully collected by the teaching assistants, before they were ordered alphabetically by a sorting machine.

Question 10 (2 marks)

Passive Version:Many of my classmates found the exam too difficult to complete, but it was still considered by them to be a fair one. I found it quite easy overall, but some questions had obviously been designed to be very difficult by the instructors.

Question 11 (8 marks)

Are the following sentences written in the active or passive voice? Copy and paste the whole set of eight sentences and then answer either 'active' or 'passive' for each one.

Sentence 1: Students often find it difficult to differentiate between the active and passive voices.
Sentence 2: Writers and presenters know how important it is to learn these differences, however.
Sentence 3: In most cases, the active voice is preferred by communicators.
Sentence 4: People generally express their thoughts more concisely when they use the active voice.
Sentence 5: For this reason, it is believed by us (as instructors) that long-winded, passive sentences are harder to follow.
Sentence 6: Yet there are times when you should preferentially use the passive voice.
Sentence 7: Some of these examples will be highlighted by instructors (and in these guides) over the course of your studies.
Sentence 8: But when you are in doubt, we encourage you to use the active voice.

Verbs and the active and passive voice

By now you should feel more comfortable changing the style of a sentence from active to passive, and vice versa. As a quick recap, recall that you use the active voice when the subject performs the action on the object. For example, you might write: “Professional footballers will kick footballs harder than amateurs.” Now recall that to make the above sentence passive you would ensure that the subject has the action performed on it (so that it is effectively doing nothing). For example, you would write: “Footballs will be kicked harder by professional footballers than amateurs.”

Look closely at the two sentences and see that the verb (the action/doing word) changes form between the active and passive voice. In the above example, the verb - ‘to kick’ – changes from ‘kick’ in the active voice to ‘kicked’ in the passive voice.

Depending on the verb, and the structure of the sentence, it might not always be different. However, it is very important that you learn to use the correct form of a verb when using one style of voice, and particularly if you write sentences that switch simultaneously between the two.

Question 12 (10 marks)

Fill in the blanks in the following sentences with the correct form of the verb attached to each topic:

A: Topic = evolution, verb = to specialize

Active: Over time, different bird species will [?????] in eating one type of seed.
Passive: Different bird species may be [?????] in eating one type of seed.

B: Topic = competition, verb = to eat

Active: In our study, we noticed that stronger individuals [?????] the best food because they out-competed the weaker ones.
Passive: Weaker individuals may have been forced to [?????] poorer quality food than stronger ones because they were out-competed.

C: Topic = designing an experiment, verb = to begin

Active: The researcher [?????] reading literature a long time ago to get ideas about what sort of experiment to design.
Passive: The process of designing an experiment was [?????] by the researcher reading literature to get ideas about the general topic.

D: Topic = global warming, verb = to prevent

Active: Many climatologists believe it is now impossible to [?????] global warming.
Passive: [?????] global warming is now believed to be impossible by many climatologists.

E: Topic = laboratory experiments, verb = to replicate

Active: My professor thinks that [?????] the experiment will improve the strength of the conclusions.
Passive: I was asked to [?????] the experiment by my professor as it is thought that this will improve the strength of the conclusions.

The suggested solutions of these activities require a password for access. We encourage interested instructors to contact Dr. Jackie Stewart and the ScWRL team to obtain access. Please fill out the Access Request and Feedback Form to inquire about resources you are interested in.

Click here for the suggested solutions password protected page for: Version 1 and Version 2 Solutions

Active and Passive Voice: Student In Class Activity

Before you can purposefully structure your writing in the active (or passive) voice, you must be able to understand which elements of each sentence comprise the subject and object. Once you are able to do this, you will be able to re-order your sentences to write in the style that is most appropriate for the situation.

Recall from the pre-class activity that in the active voice, the subject of the sentence performs the action on the object, whereas in the passive voice, the subject of the sentence is acted upon (it effectively does nothing itself).

A handy hint: let the verb point the way

To know what the action in the sentence is, just focus on how the verb (the doing word) explains the content in the sentence. For example, consider the following sentence.

“Pests destroy crops.”

  1. Look for the verb first
  2. Find the subject and object by considering whether the action in the verb is being actively or passively performed.

Pests destroy crops.”

In the above example, the action of the verb (from ‘to destroy’) is being actively performed (these pests are doing the destroying in this sentence). This is therefore an active voice sentence.

For it to be passive, the action of the verb would have to be performed on the subject (the pests would not directly be doing the destroying). For example: “My crops were destroyed by pests.”

Activity 1 (work alone or together, 10 minutes)

For each of the five sentences below, identify the verb before also identifying the subject and object. Then use this information to decide whether the sentence is written in the active or passive voice. You can work alone or with a partner in this activity.

  1. Over 60 million years ago, a very large meteorite crashed into Earth.
  2. The exact location of the impact is still debated by some scientists.
  3. However, most experts think the crash site is in Mexico.
  4. The extinction of the dinosaurs is attributed by many palaeontologists to the impact.
  5. Dinosaurs would have been affected by sudden changes in temperature, and meteorologists recently showed that the earth’s climate changed considerably at this time.

Activity 2 (work alone or together, 15 minutes)

Below are five more sentences, but this time they are all written in the passive voice. Re-write them in the active voice and try to reduce the length of the sentences by at least a few words in each case (one benefit of using the active voice).

  1. The mice were kept in controlled conditions by the experimenters before they were removed from their cages and placed on an exercise wheel.
  2. Each mouse was weighed by the same experimenters before and after it was placed on the exercise wheel.
  3. After 12 weeks had passed, each mouse was randomly placed in one of two treatment groups; in all cases, a die was rolled by an experimenter for each mouse and if it landed on an even number the mouse was placed in the group that received a pill.
  4. If the die landed on an odd number, the mouse was placed in the treatment group that received a placebo, which was designed by the research team to look like the pill.
  5. Following another 12 weeks in their different treatment groups, each mouse was weighed again by the experimenters and average weight gain (g) was calculated by using a calculator.

* Note: There will be a brief class regroup at this stage to discuss the answers to Activities 1 and 2 *

Activity 3 (work alone, 5 minutes)

Sentences written in the active voice generally grab attention more effectively than those written in the passive voice. When people first write essays, however, they typically produce a rough draft that features all their ideas in some form of ordered chaos, rather than worrying too much about their grammar. They then edit their work to make sure the sentences, paragraphs and transitions (remember Unit 1) fit together to make a coherent argument.

Now it is time to begin thinking about editing from the perspective of writing in the style of voice that best suits the situation. To highlight the importance of this, try to write 5-6 sentences about the best science lecture you ever attended. You only have a few minutes to do this, so just write down your sentences without thinking too much about the grammar.

Activity 4 (work together, 5 minutes)

Choose a partner (or work in groups of 3 to make sure nobody is on their own) and swap your worksheets. Now work through each sentence and highlight whether it is written in the active or passive voice. When you are finished, hand it back to the author and discuss with him/her whether you both agree on the decisions you have made.

Activity 5 (work alone, 10 minutes)

Once you have agreed which style of voice you have written each sentence in, try to re-write them in the opposite style. So, for example, if you have written your first sentence in the passive voice, re-write it in the active voice to practice using both styles (Note: This is just to make you more comfortable in using both).

Activity 6 (optional, work alone)

By now, you should have one active and one passive version of each sentence. Spend some time looking at each pair and decide which style is most appropriate. This little exercise should hopefully show you the importance of re-reading and editing your sentences from this perspective to make sure they each have maximum impact.

For more help with the active and passive voice

If you are still confused about the differences between the active and passive voice, you are encouraged to view the helpful guide on this subject published by the Purdue Online Writing Lab.

Active vs. Passive Voice: In-Class Activities, Instructor Timing Guide

Please note this guide is to help you keep track of time as students work through the activities. It complements the final worksheets (and PowerPoint) but please have a look at this guide so you know when you should display certain slides. Before beginning Activity 1, you should have students read the preamble (on worksheets) to remind them of the differences involved in using the active and passive voice.

Activity 1 (work alone or together, 10 min)

You should allow a total of 10 minutes for students to complete Activity 1.

Activity 2 (work alone, 15 min + 5 min for instructor to show/discuss answers, total time elapsed =30 min)

You should allow 15 minutes for students to complete Activity 2, before spending a further five minutes discussing the solutions to Activities 1 & 2 (PowerPoint slides #4, 5, 6 and 7) so that they can all see what the correct answers were (and some examples of re-written sentences). You could ask students for examples that used even fewer words than the solutions.

  1. You should stress that there are multiple right answers for Activity 2, but the key is in making the original versions more concise by using the active voice.
  2. You should stress it is important to stick to time. If students do not finish all the sentences in Activity 2, they can always complete this part at home.

Activity 3 (work alone, 5 min, total time elapsed = 35 min)

You should allow five minutes for students to complete Activity 3 (they only have to write five or six sentences about the best science lecture they ever attended.

Activity 4 (work together, 5 min, total time elapsed = 40 min)

You should allow 5 minutes for students to work together to complete Activity 4.

Activity 5 (work alone, 10 min, total time elapsed = 50 min)

You should allow 10 minutes for students to complete Activity 5 (they might need less time as they are just altering their own sentences to the opposite style of voice they originally wrote them in).

Activity 6 (optional/take home)

This Activity simply asks students to critique each sentence they have written. For each topic, they will have one active voice sentence and one passive voice sentence. The idea here is to get them to appreciate that different styles are more or less appropriate depending on the content (it is not always a bad idea to use the passive voice). Also draw attention to the suggested link on their handouts for more information on this topic.

* Please note that when piloted in Term 1, 2013, some classes completed everything in the allotted time and some failed to get past Activity 4 *'

* If students are taking time to complete these activities, feel free to let them. As long as they complete Activities 1 – 4, they can take Activities 5 and 6 home to reflect on the messages of this hands-on unit, and gain more practice in swapping between styles of voice. *

* This is one of the harder hands-on units, so it is important not to rush. Working through activities 1 – 4 should give everyone more confidence working with the active and passive voice. *

The suggested solutions of these activities require a password for access. We encourage interested instructors to contact Dr. Jackie Stewart and the ScWRL team to obtain access. Please fill out the Access Request and Feedback Form to inquire about resources you are interested in.

Click here for the suggested solutions password protected page for: In-class Activities Solutions

Version 1

Active and Passive Voice: Student Post-Class Activities

These post-class activities have been designed to give you further practice in spotting sentences written in the active and passive voices, writing in the different styles of voice, and choosing the style appropriately depending on the content of your writing.

Questions 1, 2, 3, 4, and 5 (1 mark each, 5 marks total)

For these questions, read each sentence below and decide whether it is:

A. Written in the active voice first and the passive voice second
B. Written in the passive voice first and the active voice second
C. Written in the active voice only
D. Written in the passive voice only.

Question 1 (1 mark)

Lucy convinced her brother to take the survey she developed for statistics, but she was later informed by her professor that such a move is a type of bias.

Question 2 (1 mark)

Mother lions carry their cubs from place to place before they walk and run everywhere on their own.

Question 3 (1 mark)

Frogs are considered to be indicator species by scientists, as their relative presence or absence indicates the health of the particular ecosystem.

Question 4 (1 mark)

Sediments are formed by the weathering of rocks, precipitation reactions, or other biological processes.

Question 5 (1 mark)

Meteorites that hit the Earth cause impact craters that are approximately ten times larger than the diameter of the meteorite.

Questions 6 and 7 (2 marks each, 4 marks total)

Study the sentences below, which are written in either the passive or active voice. Your task for these questions is to decide which voice is more effective for the given topic. Copy your answer (1 mark) and justify (in a few words) why you chose this sentence (1 mark). Hint: Choose one of the two sentences for each question and state whether it is active or passive, before saying why you think it is more suitable than the other version.

Question 6 (2 marks)

A. The Human Genome project was completed in 2003, two years ahead of schedule.
B. Many international organizations worked together to complete the Human Genome Project in 2003, two years ahead of schedule.

Question 7 (2 marks)

A. An unknown group of individuals dumped hundreds of pollutants in the river over the weekend, which is a concern for wildlife biologists.
B. Hundreds of pollutants were dumped into the river over the weekend, which is a concern for wildlife biologists.

Questions 8, 9, and 10 (2 marks each, 6 marks total)

Read the three active voice sentences below. Now re-write each one in the passive voice (1 mark) but try hard to use fewer words than in the original sentences without losing important/necessary detail (1 mark). This will give you practice in writing concisely even when you have to use the passive voice. For each answer, simply include your re-written statement and the word count. Hint: In reality, you may not want to write these sentences in the passive voice, as they may be more appropriate in the active voice. However, as in the pre-class activities, this question will give you practice in re-writing sentences in the opposite style of voice, which is an important skill to master.

Question 8 (2 marks)

Animals sometimes alter their natural behaviour when researchers tag them with monitoring equipment because the equipment often increases drag. Hint: Try to use fewer than 19 words.

Question 9 (2 marks)

Tagged research equipment causes even more drag for juvenile animals, as compared to adults. Hint: Try to use fewer than 14 words.

Question 10 (2 marks)

Research equipment will collect more realistic data when researchers select tags that have the least impact on the target organism. Hint: Try to use fewer than 20 words.

Question 11, 12, and 13 (2 marks each, 6 marks total)

These questions have been designed to give you practice in:

  1. Reducing the length of passive voice sentences to make them more concise
  2. Changing them to active voice sentences to further reduce the word count.

To begin, read the passive voice sentences below and try to remove any unnecessary words from them while keeping them in the passive voice (1 mark each). Hint: Simply remove words at this stage, rather than re-writing sentences. Then try to re-write these sentences in the active voice (1 mark each).

Question 11 (2 marks)

A waterproof, photo-luminescent material, which was designed by researchers as a glow-in-the-dark coating for roads, has been created by a UK-based company.

Question 12 (2 marks)

During the day, light is absorbed by the material resulting in a glow to be emitted from the material at night.

Question 13 (2 marks)

In addition to making roads safer at night, it is thought by the company, as well as current consumers, that the coating could provide enough light so that street lamps could be removed to save money and energy.

Question 14 (4 marks)

Choose a topic in science that you are very interested in and write a paragraph about it, incorporating three or four sentences. Note that you do not need to write a long answer (less than 150 words will be fine), but make sure you write at least one sentence in the active voice and at least one in the passive voice. Try to make sure you choose the style of voice to be appropriate for each sentence though!

This activity is designed to give you practice in moving interchangeably between the active and passive voice in sentences in the same paragraph, and to make you think more about the circumstances in which it is appropriate to use each style.

Version 2

Active vs. Passive Voice: Student Post-Class Activities

These post-class activities have been designed to give you further practice in spotting sentences written in the active and passive voices, writing in the different styles of voice, and choosing the style appropriately depending on the content of your writing.

Questions 1, 2, 3 and 4 (1 mark each, 4 marks total)

Answer the following questions that focus on the differences between the active and passive voices, and on the philosophy of using each style.

Question 1 (1 mark)

Which of the scenarios below is a more suitable candidate to be written in the passive voice?

Scenario A: You are writing about the art of Leonardo Da Vinci after visiting a gallery showcasing his work.
Scenario B: You are writing about some graffiti you discovered on your locker but do not know who drew it.

Question 2 (1 mark)

Justify (in a few words) why you choose either Scenario A or Scenario B as the more suitable candidate in Question 1 (above).

Question 3 (1 mark)

Complete the following sentence:

Generally speaking, using the active voice in scientific writing will result in:

A: More concise sentences with less specific detail in them
B: More concise sentences with at least as much specific detail in them
C: Less concise sentences with at least as much specific detail in them
D: Less concise sentences with less specific detail in them

Question 4 (1 mark)

Study the following sentence:

“Ben was encouraged by his friends to run for science president, but he decided not to make an official application.”

This sentence features:

A: The active voice only
B: The passive voice only
C: The active voice first and the passive voice second
D: The passive voice first and the active voice second

Question 5 (4 marks)

Read the four sentences written in the active voice below. For each blank space, match the appropriate reason that explains why it would be wise to write the same/similar information in the passive voice. The reasons are below the sentences on this page.

Michael made the critical mistake of forgetting to add warm water to the tank after 30 minutes had passed. This sentence would be better if written in the passive voice, because it [?????].

The overall trend in the data clearly shows that activity rate increases when temperature also increases. This sentence would be better if written in the passive voice, because it [?????].

Some specialist group, individual, or university team should clean the laboratory. This sentence would be better if written in the passive voice, because it [?????].

Somebody with access to the laboratory stole my cell cultures yesterday evening. This sentence would be better if written in the passive voice, because it [?????].

Match the following reasons to the sentences by copying and pasting them into the correct blank space in the answer box:

Reason 1: includes unnecessary detail to confuse the main purpose of the sentence.
Reason 2: needlessly highlights an unknown ‘doer’ of the action.
Reason 3: makes a subjective statement sound objective.
Reason 4: makes the statement unnecessarily personal.

The above question was designed to highlight that there are occasions when using the passive voice is not only acceptable but actually preferable to the active voice. Whenever you communicate anything in science (and in any format), your number one goal should be to make sure it is easy to understand. For this reason, writing concise sentences is a very important skill to master. Having said this, you can very occasionally integrate active and passive voice sentences into the same paragraphs (and even sentences) in the right circumstances.

Questions 6, 7, 8 and 9 (2 marks each, 8 marks total)

Re-read the four active voice sentences in Question 5. Now re-write each one in the passive voice but try hard to use fewer or the same number of words as in the original sentences without losing important/necessary detail. This will give you practice in writing concisely even when you have to use the passive voice.

For each answer, simply include your re-written statement and the word count.

Question 6 (2 marks)

Sentence 1: “Michael made the critical mistake of forgetting to add warm water to the tank after 30 minutes had passed.”

Question 7 (2 marks)

Sentence 2: “The overall trend clearly shows that activity rate increases when temperature also increases.”

Question 8 (2 marks)

Sentence 3: “Some specialist group, individual, or university team should clean the laboratory.”

Question 9 (2 marks)

Sentence 4: “Somebody with access to the laboratory stole my cell cultures yesterday evening.”

Questions 10, 11, 12 and 13 (1 mark each, 4 marks total)

Read the short paragraph below about the effect of randomness in dictating how many individuals of each species are found in a given environment at any time. For questions 10, 11, 12 and 13, you need to consider each sentence separately and say whether the active and/or passive voices are used (and in which order).

For example, for each question you must say whether the sentence features:

Option A: The passive voice only
Option B: The active voice only
Option C: The passive voice first and the active voice second
Option D: The active voice first and the passive voice second

“In any given environment, the number of individuals present that belong to different species will be dictated by a combination of abiotic and biotic factors. For example, predators reduce the numbers of herbivores, whereas favourable environmental conditions cause populations to grow. However, scientists fail to predict exact numbers; this is because random events that cannot be predicted by anyone also impact populations. Any random event can cause the numbers of one species to increase, while another species can be negatively impacted by the same unpredictable event.”

Question 10 (1 mark)

Sentence 1: In any given environment, the number of individuals present that belong to different species will be dictated by a combination of abiotic and biotic factors.

Question 11 (1 mark)

Sentence 2: For example, predators reduce the numbers of herbivores, whereas favourable environmental conditions cause populations to grow.

Question 12 (1 mark)

Sentence 3: However, scientists fail to predict exact numbers; this is because random events that cannot be predicted by anyone also impact populations.

Question 13 (1 mark)

Sentence 4: Any random event can cause the numbers of one species to increase, while another species can be negatively impacted by the same unpredictable event.”

Question 14 (5 marks)

Choose a topic in science that you are very interested in and write a paragraph abut it, incorporating five or six sentences. Note that you do not need to write a long answer (100-150 words will be fine). Make sure you write sentences in both the active and passive voice, but make sure you choose the style of voice to be appropriate for each sentence.

This activity is designed to give you practice in moving interchangeably between the active and passive voice in sentences in the same paragraph, and to make you think more about the circumstances in which it is appropriate to use each style.

The suggested solutions of these activities require a password for access. We encourage interested instructors to contact Dr. Jackie Stewart and the ScWRL team to obtain access. Please fill out the Access Request and Feedback Form to inquire about resources you are interested in.

Click here for the suggested solutions password protected page for: Version 1 and Version 2 Solutions

 Active vs. Passive Voice In-class PowerPoint

Timing Guide

Pre-Class Activities: Version 1  |  Version 2

In-class Activities

Post-class Activities: Version 1  |  Version 2


The suggested solutions of these activities require a password for access. We encourage interested instructors to contact Dr. Jackie Stewart and the ScWRL team to obtain access. Please fill out the Access Request and Feedback Form to inquire about resources you are interested in.

Click here for suggested solutions password protected page for: Pre-class activity, Post-class activity, and In-class activity solutions

References

1: Day RA. How to write and publish a scientific paper. 5th ed. Oryx Press. 1998.

2: Millar N, Budgell B, Fuller K. ‘Use the active voice whenever possible?’: The Impact of Style Guidelines in Medical Journals. App Ling. 2013; 34(4): 393-414.

3: Humphrey JD, Holmes JW. Style and Ethics of Communication in Science and Engineering. San Rafael, California: Morgan & Claypool. 2009.

4: Leong PA. The passive voice in scientific writing. The current norm in science journals. JCOM. 2014; 13(1): A03.