Subject–Verb Agreement

Subject–verb agreement means that the form of a verb must correspond appropriately with its subject, particularly in number and person.

In the present tense, third-person singular subjects usually take a verb ending in -s, while plural subjects normally take the base form:

The student works hard.
The students work hard.

With the verb be, the forms are different:

I am ready.
He is ready.
They are ready.

Identifying the True Subject

A common error occurs when words between the subject and verb distract the writer:

The list of names is on the desk.

The subject is list, not names, so the singular verb is is correct.

Similarly:

The quality of the products has improved.

The phrase of the products does not change the number of the subject quality.

Compound Subjects

Subjects joined by and generally take a plural verb:

Ali and Ahmed are brothers.

But a compound expression may represent a single idea or unit:

Bread and butter is my usual breakfast.

Subjects joined by or or nor require particular attention:

Either the teacher or the students are responsible.
Either the students or the teacher is responsible.

When the subjects differ in number, the verb commonly agrees with the nearer subject in such constructions.

Indefinite Pronouns

Some indefinite pronouns normally take singular verbs:

Everyone is ready.
Each of the students has a book.
Neither answer is correct.

Others are plural:

Many are absent.
Several have arrived.

Some can be singular or plural depending on the noun that follows:

Some of the water is gone.
Some of the students are absent.

Collective Nouns

Collective nouns such as team, family, committee, and government may take singular or plural agreement depending on meaning and variety of English.

The team is winning.

Here the team is viewed as one unit.

In British English, plural agreement can occur when the individual members are emphasized:

The team are arguing among themselves.

The important principle is to maintain logical and consistent agreement.