Revising and Editing

Reconsidering your ideas, examining your paragraphs, checking your style and grammar.

Parallel Structure in a Series
Nouns, Verbs, Gerunds, and Infinitives

If you have two or more words in a series, they must be the same part of speech. For example, if the first word of the series is a noun, the rest should be nouns as well. By using words of a different part of speech in a series, you create incorrect parallel structure.

Example 1:

	People infected with HIV frequently exhibits one or more of the following symptoms: headaches, lightheadedness and they are dizzy.
	People infected with HIV frequently exhibits one or more of the following symptoms: headaches, lightheadedness, and dizziness.

The second sentence is correct because all of the symptoms are nouns.

Example 2:

	There is nothing more important than being healthy, having an excellent education, and to look handsome.
	There is nothing more important than being healthy, having an excellent education, and looking attractive.

The second sentence is correct because all of the words in the series are gerunds (the -ing form of a verb that is used as a noun).

Example 3:

	The doctor advised Robert to take a lot of vitamins, drink a lot of fluids, and to rest a lot when he gets a cold.
	The doctor advised Robert to take a lot of vitamins, to drink a lot of fluids, and to rest a lot when he gets a cold.

The second sentence is correct because all of the words in the series are infinitives.

Remember to keep the same structure throughout the sentence and to be consistent with the parts of speech.

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