ACT® · English: Usage Conventions
Agreement with Text Between Subject and Verb
The verb must agree with the real subject, not with whatever noun happens to sit right in front of it. Cross out the phrase or clause between them to see the subject clearly.
The English section tests subject-verb agreement by hiding the subject behind extra material. A sentence like 'The box of nails is heavy' feels wrong to the ear because 'nails' sits right before the verb, and plural nouns pull toward plural verbs. But 'nails' is not the subject. It is the object of the preposition 'of', stuck inside a phrase that describes the box. The box is the one thing being discussed. The box is heavy, singular verb, no matter how many nails are inside it.
The fix is mechanical: cross out the prepositional phrase. 'The box of nails' becomes 'The box', and now the subject sits right beside its verb where your ear can judge it correctly. This works because a prepositional phrase can never contain the subject of its own sentence. 'Of nails', 'beside it', 'in the storeroom' - all of these are just descriptions riding along, and none of them can be what the sentence is actually about.
The same move works when the interrupter is a full clause instead of a short phrase. 'The proposal that the reviewers criticized most sharply was withdrawn on Friday' still has one subject, 'the proposal', even though an entire clause with its own subject and verb sits between them. Cross out 'that the reviewers criticized most sharply' and 'the proposal was withdrawn' sits there plainly. This is the same skill tested elsewhere in usage conventions: find the one word a rule actually governs, and ignore the noise built around it.
Key terms
- Subject
- The noun that the main verb of the sentence actually agrees with and describes.
- Prepositional phrase
- A phrase starting with a word like of, in, or beside that can never contain the sentence's subject.
- Subject-verb agreement
- The rule that a singular subject takes a singular verb and a plural subject takes a plural verb.
- Interrupter
- A phrase or clause placed between the subject and verb that must be ignored when checking agreement.
Watch it explained
- How it worksHow does crossing out a prepositional phrase leave the real subject sitting beside its own verb?
- Common mistakeWhy isn't 'nails' the subject of 'The box of nails', when it is the word right before the verb?
- Going furtherWhat changes when the words between subject and verb form a whole clause instead of a short phrase?
Check yourself
End of topic.