Agreement (Subject-Verb and Pronoun)
What to know
Agreement means subjects match verbs in number and pronouns match their antecedents in number and gender. Find the true subject by stripping prepositional phrases ("The box of receipts was ..."). Compound subjects joined by "and" take plural verbs; those joined by "or/nor" agree with the nearer subject. Indefinite pronouns like each, everyone, anybody, nobody, either are singular. Collective nouns (team, committee) are usually singular in American usage. Pronoun case matters: subject pronouns (I, he, they) for subjects, object pronouns (me, him, them) after prepositions and verbs.
Traps
Intervening phrases are designed to mislead ("Each of the players was ready"). "Every" and "each" before a noun keep it singular. Watch inverted sentences ("There are three reasons..."). Also avoid vague pronoun reference ("they" with no clear antecedent) and shifts in person.
Rule of thumb
Cross out everything between the subject and verb, then read the sentence aloud. For pronouns, name the antecedent and substitute it to test.
Worked example: "Neither the manager nor the employees was/were informed." With "nor," the verb agrees with the nearer subject, "employees," so "were" is correct. For pronouns: "Between you and I/me, the plan is risky" → after a preposition, use "me."