The subject and the verb must agree in number.  A singular subject takes a singular verb, and a plural subject takes a plural verb. Keep in mind that the third person singular present tense verb usually has an "s" on the end of it, but it is single.

1.    No matter how many words are in between the subject and the verb, they must agree.  Nouns found inside of prepositional phrases are often mistaken for the subject of a sentence:

        Sara, along with her sisters, goes to the mall often. (Sara is the subject, so the verb is "goes.")
        The color of the flowers is awesome. (Color is the subject, not flowers, so the verb is "is")

2.    When two or more subjects are joined by "and," the verb is usually plural:

        Sara and Paula are going to the mall.

     If "each" or "every" comes before a subject connected by "and," the verb is singular.

        Each dog and cat is eating its food.
 
3.    Most indefinite pronouns are singular and, therefore, take a singular verb. Any indefinite pronoun that ends in "-one," "-thing," or "-body" is
always singular:

        Everybody is going to the mall.
        Someone calls my house every night after 10:00 p.m.

    The SAMMAN pronouns (some, any, more, most, all, none) can be singular or plural, depending on how they are used in the sentence. To     decide if the SAMMAN pronouns are singular or plural, look at the word at the end of the prepositional phrase following the pronoun:

        Most of the citizens plan to get involved. ("Citizens" is plural, so you should use a plural verb.)

        Some of the debris has been hauled away. ("Debris" is singular, so you should use a singular verb.)

4.    When subjects are joined by "or," "either/or," "nor," or "neither/nor,"  the verb agrees with the subject nearer to it:

        Neither the dogs nor the cat eats in the kitchen.
        Either the dog or the cats eat in the kitchen.

5.    Read sentences very carefully if the subject is the name of a group (or a collective noun). Examples are words like chorus, audience, committee, or class.  Subjects that are the names of groups are singular if all members of the group are doing the same thing at the same time; if members of the group are doing different things or at different times, then the subject is plural:

 For example:    1.     The jury reaches a verdict.

    2.     The jury go home after the trial.

In the first sentence, the members of the jury all agree on the same verdict at the same time (singular).

In the second sentence, the members of the jury separate to go to different homes (plural).

 6.    When the sentence is a question or the sentence starts with "here" or "there," the subject will be found after the verb. However, the verb
must still agree with the subject:

        Are Sara and her friends going to the mall?  ("Sara" and "friends" are the subjects, so "are" is the verb.
 
        Here are several rules that you must follow. ("Rules" is the subject, so "are" is the verb.)

7.    Some nouns that end in "s" are considered singular and take a singular verb:

        mumps, measles, news, politics, economics, ethics

8.    Subjects that are units of measurement are usually singular because two pounds of sugar is just one amount, three hours is just one length of time, ten dollars is just one amount of money, and six miles is just one distance. Don't get confused and think that all numbers are affected by this rule. The only numbers affected are those numbers followed by a word that names a type of measurement such as weight, time, length, or currency.

Make sure to proof all of your sentences for subject/verb agreement.

 

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