Analytical Writing for Science and Technology
Copyright © 1996 by T. M. Georges.

Lesson 12

Put Active Verbs to Work for You


In this Lesson:

In this lesson, you'll learn how to eliminate most of the passive verbs in your writing. It's not that passive verbs are bad in themselves, but when they are overused, they hide the identity of the doer, they invite roundabout sentence construction, and they lead to awkward, unnatural-sounding prose. At least half of the passive verbs in scientific and technical writing should be changed to active forms.


First, let's make sure you know how to recognize passive verbs when you see them. Look at these two sentences:

Frisky ate my homework.

My homework was eaten by Frisky.

In the first sentence, the subject of the sentence, Frisky, is also the doer of the action -- in this case, eating. The verb ate is an active verb.

In the second sentence, the subject of the sentence, homework, is the recipient of the action, and Frisky, the doer, is the object of the preposition by. The verb was eaten is a passive verb.


PASSIVE VERB --- was eaten by

Notice that the flow of action in the first (active) sentence seems more natural:

Frisky > ate > homework

whereas the order in the second (passive) sentence seems "backwards":

Homework < was eaten < Frisky

Notice also that the word by often (but not always) follows a passive verb. You can use by as a signpost -- there's usually a passive verb nearby.

To make sure you understand, check the one of these two sentences that has an active verb.

The explosion was caused by a kerosene lamp.

The technicians demanded longer coffee breaks.

The first sentence has a passive verb was caused, and the second sentence has an active one demanded. Notice the flag by in the first sentence?

Now let's practice converting passive verbs to active ones. Each of the following sentences has one passive verb. On your printed copy of this lesson, use your pink highlighter to mark each passive verb, then rewrite each sentence so that the verbs are all active.

A voltmeter was used by the electrician to monitor the line fluctuations.

A new computer has been installed by the accounting section.

Sixty-five new comets were discovered by amateur astronomers last year.

The wiring in the electric chair was found to be faulty.

When the atmospheric pressure drops, the barometer needle is observed to swing to the left.

A micrometer was used to make sure the machine parts were within tolerances.

Did you notice that finding a new subject for these sentences was easy when the word by followed the passive verb? You just used the noun that followed by. But when no by was present, you may have had to imagine a subject. Another tip for finding passive constructions is to look for forms of the verb to be, for example, is, am, be, being, were, was, been.


In the last lesson, we learned how to substitute concrete nouns for abstract ones. Passive verbs seem to attract abstract nouns, so that when you eliminate one you often have to change the other.

Here are some sentences with abstract noun/passive verb pairs. On your printed copy of this lesson, mark the abstract nouns in green, as before, then mark the passive verbs in pink. Finally, rewrite the sentence to remove both.

The practice of filling out work orders in triplicate is disliked by the machinists.

The flexibility of the new computer was emphasized in the advertisement.

The ability of the aircraft to survive spears and arrows was stressed in the design.

The chief measure of the new economic program's success will be indicated in the reduction of inflation.

It is recommended that adequate shielding be placed around the reactor.

Separation of the steel from the brass is performed magnetically.


When you decide to write a sentence with a passive verb, you often get trapped into using awkward constructions like:

  • through the use of
  • in order to
  • on the part of
  • as to whether
  • in the case of
  • for the purpose of

In the following sentences mark and remove each passive verb, noticing how, at the same time, you no longer need such awkward constructions:

In the laboratory, a high safety record is achieved through the use of double-shielded walls.

A new power supply was required in order to fix the robot.

No knowledge of calculus is required on the part of the students.

The pilot was questioned as to what action would be taken in the event that he saw a UFO.

When disinfectants are used in connection with hospital cleaning programs, supplies seldom become contaminated.


Sometimes you want to emphasize the object of an action more than the subject. Then you'll want to place the object of the action first in the sentence (that is, make it the subject of the sentence). That usually requires a passive verb. Look at these two sentences:

(1) The Cosmic Company installed a new word processor.

(2) A new word processor was installed at the Cosmic Company.

Which sentence emphasizes the word processor, and which focuses attention on the company? You naturally expect the sentence following (1) to continue talking about the Cosmic Company, whereas the one following (2) would logically talk some more about the word processor.

Suppose you wanted to write about the 85% accuracy a forecaster achieved in predicting snowstorms. How would you write the sentence to emphasize the forecaster?

Now suppose you were writing mainly about snowstorms and wanted to emphasize them?

Can you see how the emphasis you want affects how you choose the subject of each sentence and consequently your choice of an active or passive verb?


Weak verbs like do, make, perform, have and forms of the verb to be convey practically no sense of action, and so waste the function of the verb as the sentence's power source. Whenever you can, substitute verbs that create a clear sense of action. This is easy when you see nouns that are really verbs in disguise.

Look at these examples of weak verbs coupled with nouns that are really strong verbs in disguise. Write in the blank after each one the strong verb that you can substitute.

make a recommendation
formulate an argument
raise an objection
make restitution
express resentment
arrive at a conclusion
perform an analysis
develop a plan
exercise conformity
undertake a development
find a solution
make a decision

Find a few paragraphs you have written recently and use your pink highlighter to mark all the passive verbs. Notice how the passive verbs have attracted awkward constructions and abstract nouns. Rewrite those paragraphs using the techniques you have learned in this lesson. Get into the habit of using your pink highlighter to flag passive verbs in your own writing.


As you write, keep in mind that the word passive means the same as submissive, inactive and inert. Are these the qualities that you want your writing to have? If more than about one-third of your verbs are passive, you writing probably sounds stilted and unnatural and doesn't inform as forcefully as it could. Substitute strong verbs for weak, inert verbs whenever you can.

The next lesson describes a powerful tool for analyzing and specifying the relations among details -- the dependent clause.

-- End of Lesson 12 --

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