In English the subject and the verb must agree in number. This is an elementary rule of sentence grammar, but students run afoul of it all too often, in part because word processors make it possible to change a few words without retyping a sentence in its entirety. If you write with a computer, be sure to reconsider carefully any sentence in which you have made changes.
Problems with agreement often arise when a writer is trying to avoid sexist language. "Everyone should bring their book," for example, confuses singular and plural forms. A better solution may be to use the plural consistently when discussing groups or classes: "All students should bring their books." Lack of agreement in the use of pronouns can call attention to a writer's struggle to avoid sexist language. Learn to use gender-neutral language effortlessly.
Problems with agreement can also develop in sentences with complicated or deceptive structures, especially compound subjects (two or more nouns linked by "and"). Here is a case in point:
The magnitude and volatility of recent market activity makes effective forecasting difficult.Read carelessly, this sentence may not seem erroneous, but in fact its singular verb ("makes") is out of agreement with its plural, compound subject ("magnitude and volatility"). The sentence should read:
The magnitude and volatility of recent market activity make effective forecasting difficult.Always read your draft aloud as one stage of revision. Many writers find it much easier to catch problems of agreement in this way than by silent proofreading.
See also Purdue handouts on making subjects and verbs agree and using pronouns clearly.
Copyright 1996 Yale University. Revised on Sunday, May 19, 1996