Linking verbs and adjectives

Here is a question that came up for a colleague on the news desk this week. A summary head said, in part, “The man was acting erratic.” Another editor thought the last word should be “erratically.” Did the sentence need an adjective to describe the man or an adverb to describe his actions? This question hinges on whether “act” can be a linking verb.

Linking verbs imply a state of being. They link the subject to a noun that renames the subject or an adjective that describes the subject. Often, a linking verb is a form of “to be.” The children are happy. The marriage was troubled. Verbs of the senses — look, taste, smell, sound, feel — are often linking verbs. So sometimes are appear, seem, become, remain, look and grow. The children seem happy. The marriage appears troubled.

“Act” is not usually listed among the linking verbs. But notice how we use it as one: The children acted happy when their parents told them about the planned vacation. An adjective, “happy,” follows “acted.” But we also use “act” with adverbs. The chief executive officer acted aggressively when the stock price plummeted.

If we use “act” in its meaning of “to appear to be,” we use it as a linking verb and, therefore, follow it with an adjective. If we use “act” as an action verb meaning “to do something,” then we need an adverb.

So what about “was acting erratic”? If we substituted “was being” or “was appearing,” then the choice is “erratic,” and I do believe that is what the meaning of the verb was in this case.

Here is a link to a discussion at a site called EnglishForum.com about “act” as a linking verb. The Tongue Untied, a guide to grammar, punctuation and style for journalists from the University of Oregon, has detailed explanation of linking verbs.

This article was originally posted by the Raleigh News & Observer, a subsidiary of The McClatchy Co.; is posted here to provide continuity; and is copyright © 2011 The News & Observer Publishing Company, which reserves the right to remove this post.