Overview
Agreement connects a sentence's finite verb to its grammatical subject. The nearest noun is not necessarily the subject: phrases after of, relative clauses, and inverted word order can place another noun closer to the verb. Begin by identifying the clause and asking who or what performs its action. Then decide whether that subject is treated as one unit or as more than one.
Consider The box of application forms is on the counter. Box is the head of the subject; of application forms tells us which box. Removing that phrase produces The box is on the counter, making the singular verb easy to hear. Choosing are because forms is plural follows proximity rather than grammar. The same method applies to The number of missing files has decreased: number, not files, controls has. Each of the notebooks likewise selects one notebook at a time, so each contains. Neither folder contains is another singular construction.
Subjects joined by and ordinarily describe two entities: The curator and her assistant check the display. An either/or construction works differently; in Either the instructor or the tutors are available, the nearer subject tutors controls the verb. In There are two damaged shelves, there introduces the sentence but shelves is the plural subject. Looking only at the beginning would miss the real agreement relationship.
Different clauses can require different verbs. Lena is one of the students who arrive early has a singular main-clause subject, Lena, and a plural antecedent for who, students. The sentence identifies Lena as a member of the arriving group. Choosing who arrives because Lena is singular ignores the subject inside the relative clause. Read and test each clause separately.
Meaning also matters. Ten minutes is enough treats a measured duration as one amount. The committee reviews the proposal as a single group treats a collective noun as a unit in American edited prose. The lesson does not mean that every plural-looking expression must be singular or that collective nouns have one interpretation in all varieties of English. Use the sentence's stated meaning and context.
On a new item, mark the subject, temporarily remove intervening modifiers, and match the finite verb. Restore the whole sentence to confirm that the meaning survives. For clauses with who or that, identify the antecedent within the actual construction. A useful final check asks which specific noun controls each verb, rather than whether the option merely sounds familiar.
Apply the method to a complete new context
Read the full sentence and its context before choosing an answer.
Sentence editing: agreement
A team newsletter reports that the head coach planned the season schedule with help from her assistants.
Which sentence is correct? A. The coach, along with her two assistants, have planned the season schedule. B. The coach, along with her two assistants, are planning the season schedule. C. The coach, along with her two assistants, were planning the season schedule. D. The coach, along with her two assistants, has planned the season schedule.
The supported answer is D: The coach, along with her two assistants, has planned the season schedule. Set aside the phrase along with her two assistants and the subject is coach, which is singular. Choice A treats along with as if it were and, creating a compound subject the sentence does not have.
Set aside any phrase between the subject and the verb, then match the verb to the head noun that remains.