A subject must agree with its verb in number. This rule is simple enough, but people nonetheless struggle to follow it consistently. In short, a singular subject requires a singular verb and a plural subject requires a plural verb. In simple or short sentences, it will be more obvious. For example, “She see the sign” is obviously incorrect. However, longer or more complex sentences can be a little trickier, and boy do we like being tricky.

Here are a couple of examples:

The growing tension between two dog show judges in the recent Westminster Show have been evident to most observers, except the dachshund lovers, of course.

The group of dachshunds, who are becoming more vocal by the day, demand major changes to current barking policies.

Both sentences contain a subject-verb disagreement. In the first sentence, the subject is “tension,” which is singular. The verb should therefore also be singular, unlike in this example. The correct form should read “has been evident.”

Likewise, in the second example, “group of dachshunds” is singular and should therefore have the singular verb “demands.” It should be noted that, true to their breed, the dachshunds kept barking throughout this important lesson.