A single verb may have two or more subjects. Subjects that share a single verb are called compound subjects.

When the word and joins two subjects, the verb should usually be plural. Consider the following example:

Our cat and dog eat table scraps.

Although both cat and dog are singular words, the plural verb eat is correct because the two singular subjects are joined by the word and.

If the compound subject is modified by each or every, the verb should be singular, as in the following example:

Every student and professor enjoys spring break.

A few subjects joined by and actually describe a single thing or idea. Such expressions are singular, as in the following example:

Peace and quiet is what my mother wants at home after work.

Only and joins subjects so that they require a plural verb. Or and nor do not create plural subjects, as in the following example:

Neither the dog nor the cat has been fed.

Click the correct sentence. An orange or a grapefruit is a good source of vitamin C. An orange or a grapefruit are a good source of vitamin C.