Subjects (who or what the sentence is about) and verbs (the action or state of being) must agree.
Singular subjects must have a singular verb.
Plural subjects must have a plural verb.
Examples of Subject-Verb Agreement:
If a compound subject is joined by "or" or "nor," look at the subject closest to the verb and make the verb agree with that part of the subject.
1) These indefinite pronouns are always singular and should be paired with a singular verb: any, anything, each, either, neither, everyone, everybody, everything, someone, somebody, something, anyone, anybody, no one, nobody, nothing, one.
1）这些不定代词通常是单数，应与动词单数连用：any, anything, each, either, neither, everyone, everybody, everything, someone, somebody, something, anyone, anybody, no one, nobody, nothing, one。
2) These indefinite pronouns are always plural and should be paired with a plural verb: few, many
3) For some indefinite pronouns (some, all, none) it depends on the item that the pronoun refers to.
3）对于一些不定代词(some, all, none)，动词的单复数取决于其指代的事物。
4) Notice that some subjects may appear to be plural but are singular because they refer to one thing or a single amount of something (examples: mathematics, mumps, news)
4）一些主语以复数形式出现，但实际是单数，因为指代的是一件事情或某些事物的数量（如mathematics, mumps, news）
5) Some subjects refer to one thing, but take a plural verbs (examples: scissors, pants)
Examples of correct subject-verb agreement:
1) He runs four miles every day. (singular subject; singular verb)
2) They ride the school bus in the afternoon. (plural subject; plural verb)
3) Few of the children are here today. (plural)
4) Some of the money is missing. (singular-money is singular)
5) None of the marbles have rolled out of the circle. (plural-marbles is plural)
6) One of the nails is sticking out. (one is singular)
7) The scissors are on the table. (plural)
8) Katie or three girls walk to the office. (girls is closer, so verb is plural)
9) Is mumps caused by a virus? (singular)
10) Neither the tray nor the cupswere put away. (cups is closer, so verb is plural)