Subject-Verb Agreement

In order to make sure that your verbs (the action) correctly refer to their subjects (the noun doing the action), it is important to determine the verb tense (when the action is taking place and whether the action is ongoing or completed) and form (singular or plural) based on how many individuals are part of the subject.

VERB TENSES

Verbs used in the present tense take the base form of the verb

• ​I talk; you talk; they talk; we talk
  ​-  The exception is with the third person singular which takes the s-form (He talks; she talks)

Verbs used in the past tense generally take the ed-form

• I talked; you talked; they talked; we talked; he/she talked

Verbs used in the present and past participle take the ing, and ed-forms respectively and follow an auxiliary verb (to be, to have, etc.)

• Note how the auxiliary verbs take the s‑form in the third person singular
  -  Present participle: I am talking; you are talking; he/she is talking
  -  Past participle: I have talked; you have talked; he/she has talked 

DETERMINING VERB FORM BASED ON THE SUBJECT

Collective nouns

• Nouns such as family, choir, team, majority, minority—any noun that names a group of individual members—can either be singular or plural, depending on context and meaning.
  - The family have all gone their separate ways. (“Family” refers to multiple individuals of the group, so it’s plural.)
  - The whole family is celebrating the holidays at home this year. (“Family” refers to the group as a whole, so it’s singular.)
• Sometimes, the modifier of the headword (the primary noun in the noun phrase) determines the verb form.
  - The rest of the map was found.
  - The rest of the books were missing.

Compound subjects

• When multiple subjects are joined by and or by “both ___ and,” the subject is plural.
  - My friends and relatives are coming to the wedding.
  - Both my friends and my relatives are coming to the wedding.
• In compound subjects linked with or, “either ___ or ___,” or “neither ___ nor ___,” the verb form depends on the closer member of the pair.
  - Neither the speaker nor the listeners were intimidated by the protestors.
  - Either the class officers or the faculty advisor makes the final decision.

Quantified phrases

• Subjects with phrases such as a lot, a great many, and a large number are usually plural, not a singular as the determiner a might suggest.
  - A lot of classes were canceled.
  - A great many friends are expected to attend.
  - A large number of people were gathered outside.

 
 
 
Source: Kolln, Martha, and Robert Funk.  Understanding English Grammar.  Fifth Edition.  Boston: Allyn and Bacon, 1998.