Subject-verb agreement errors are among the most common mistakes that students make on their school papers. The general rule holds that singular nouns should accompany singular verbs, while plural nouns should accompany plural verbs. However, identifying a noun as either singular or plural can be tricky. There are several types of subject-verb agreement that students and writers must be familiar with to produce grammatically correct work.

Compound Subjects Using "And"

When a subject's sentence is made up of two or more nouns or pronouns combined by the conjunction "and," writers should use a plural verb. The sentence "Matt and Ryan were at the park." uses proper subject-verb agreement because Matt and Ryan are two people, and "were" is a plural verb.

Singular Nouns Using "Or" or "Nor"

When a subject's sentence is made up of two or more singular nouns or pronouns combined by the conjunction "or" or the conjunction "nor," the writer should use a singular verb. The subject and verb of the sentence "The red pen or the blue pen is on my desk." are in agreement because only one of the two pens is on the desk, and the verb "is" is a singular verb.

Singular and Plural Nouns Using "Or" or "Nor"

When a subject's sentence is comprised of one or more singular nouns or pronouns and one or more plural nouns or pronouns combined with "or" or "nor," the writer should use the form of the verb that agrees with whichever noun is closest to the verb. For example, the sentence "My brother or my sisters get the the mail every day." uses the plural verb "get" since the plural noun "sisters" is nearest to the verb.

Singular Subjects that Sound Plural

Writers must be careful when using the singular nouns "either," "neither," everyone," "everybody," anyone," "nobody" and "no one." Although these nouns sound as though they may refer to more than one person or thing, they are all singular and should therefore be paired with singular verbs. The sentence "Everybody likes my mom's cooking." uses the singular verb "likes" because "everybody" refers to each individual "body," or person.

Singular Subjects that End in "S"

Nouns such as "mathematics," "news," and "social studies" are singular even though they end in "s" and should be followed by singular verbs. The sentence "Mathematics is my least favorite subject." uses the singular verb "is" because mathematics is one discipline.

Collective Nouns

Some nouns such as "team," "group," "band," "family" and "class" imply the involvement of several people, but are, nonetheless, singular nouns because they refer to collective entities. The sentence "The band sings my favorite song." uses the singular verb "sings." Although the band is comprised of more than one member, the subject "band" refers to the group as a whole unit.

Accompanying Expressions

A singular subject remains singular when followed by expressions such as "with," "accompanied by," "including," and "as well" and should still be followed by a singular verb. The sentence "My wife, accompanied by her friend, volunteers at the preschool every Thursday." uses the singular verb "volunteers" because the addition of the phrase "accompanied by her friend" does not affect the singularity of the sentence's subject.