SUBJECT_ VERB AGREEMENT

Agreement means that a subject and its verb must agree with each other in
number (singular or plural), or the tenses in the main clause and subordinate clause
must agree with each other.

Basic rules of subject-verb agreement in number:
 A singular subject takes a singular verb, while a plural subject takes a plural
verb.
 When the subject is an indefinite pronoun or a noun with a quantifier, carefully
decide whether you should use a singular or a plural verb.
 When the subjects in a sentence are joined by conjunctions, a singular or plural
verb may be used depending on each particular conjunction.
The computer is
Each report is
Either you or he is
Printers are
Many companies are
Neither you nor I am

2

Agreement in tense of main clause and subordinate clause:
 When the main clause is in the present tenses,
the subordinate clause may be in various tenses.
 When the main clause is in the past tense,
the subordinate clause may be in the past tenses
Singular subject - singular verb, plural subject - plural verb
The basic rule is that a singular subject goes with a singular verb, while a plural subject
goes with a plural verb. Besides, you must use singular verbs in the following cases:
 When the subject is an uncountable noun
 When the subject is a gerund or a to-infinitive
 When the subject is a noun clause introduced by that