Using Parallel Structure

When writing a sentence, make sure all elements are parallel, or treated in the same way. Otherwise, the sentence becomes unbalanced and may confuse your readers.

Parallel Structure with Items in a Series

Incorrect: The walls in my room are painted white, gray, and they are painted pink, too.

• Discussion: This sentence is unparallel because the last item in the series is treated differently than the first two items.

Correct: The walls in my room are painted white, gray, and pink.

• Discussion: Now all the words in the series—white, gray, and pink—are single-word adjectives. They are parallel.

Incorrect: Some of my favorite activities are playing board games, dancing, and to swim.

• Discussion: This sentence is not parallel because the first two series items start with ing words and the last item starts with an infinitive phrase—to swim.

Correct: Some of my favorite activities are playing board games, dancing, and swimming.

• Discussion: Now all three ideas are expressed equally.

Parallel Structure with Comparisons

Incorrect: I think multiplying numbers is easier than to divide numbers.

• Discussion: The two items being compared are treated differently.

Correct: I think multiplying numbers is easier than dividing numbers.

• Discussion: Now the two items being compared are treated equally.

Your Turn Read the following sentences out loud with a partner. Edit them to make them parallel.

1. Some examples of marine mammals are polar bears, seals, and including sea otters.
2. Sea otters spend their days foraging for food, sunbathing on rocks, and to graze in kelp forests.
3. Did you know otters eat, sleep, and they give birth in the water?
4. Sea otters are bigger than an otter in rivers.
5. They can roam the shore and to swim at sea.
6. Oysters, mussels, and they also eat abalone.
7. Otters enjoy playing in the waves and to dive for food.
8. Thick fur, oily skin, and they have blubber to stay warm.
9. Sea otters are social, smart, and they are funny.
10. Have you ever seen an otter at a zoo or wild?