Before you do the exercises in this unit, you need to realize that the “by so and so” phrase does not always appear in a passive sentence; sometimes it is only implied. Such a sentence might still be in need of a good rewrite.

Sometimes when you are changing a sentence from passive to active, you’ll find other opportunities to make it crisper and less wordy.

And sometimes you’ll find a sentence that is passive in more than one clause. Make sure you change each passive clause when you revise it.

Finally, you’ll notice that all passive sentences are not alike. Read them aloud, and you’ll hear that some sound horrible, whereas others barely need to be rewritten or, perhaps, in some cases don’t need to be rewritten at all.

The important thing is to eliminate unnecessary passive sentences and to make your writing as active and lively as possible.

Exercise 4.4

Rewrite these passive sentences, making them active. Please use your own paper.

1. Approximately 200 pounds are gained per day by the baby calf of a blue whale.

2. An age of over 80 years has been reached by goldfish in captivity.

3. The practice of monogamy is observed by storks.

4. Its tail is used effectively as a whip by an iguana when it is threatened.

5. One-third of the total amount of canned fish in the United States is eaten by cats.

Exercise 4.5

Rewrite these passive sentences, making them active. Please use our own paper.

1. Their physical senses can be developed by human beings to a much higher degree than most people realize.

2. Enough examples from everyday life can be found by anyone to determine that this is true.

3. For example, the amount of alcohol or acid in a particular wine can be tasted by an experienced vintner to within one percent.

4. Differences between certain shades of red that are indistinguishable to the layperson can be seen by expert color technicians.

5. Just by its feel, the moisture content of bread dough can be measured by some professional bakers to within two percent of accuracy when the dough is being kneaded by them.