ACT English — grammar and usage, and how to find the subject

Most agreement errors are not errors of knowledge. A learner who can say perfectly well that a singular subject takes a singular verb will still write "the collection of rare stamps are displayed", because the word sitting next to the verb is plural and the ear follows the nearest noun. The fix is mechanical: cross out everything between the subject and the verb and read what is left.

Three questions here work on exactly that, each hiding the subject differently. One buries it behind an interrupting phrase. One inverts the sentence so the verb comes first and the subject arrives afterwards. One uses "the number of", which is singular however large the number is — and the explanation sets it beside "a number of", which is plural, because the contrast is what makes either one memorable.

Two questions concern pronouns. One turns on case after a preposition, where "between you and I" is produced by people who have been told so often to say "and I" that they apply it everywhere. One turns on number, and it is built on "each" rather than on the singular "they", deliberately: whether "their" may stand for one person is a live argument among careful writers, not a settled point, and a test bank has no business pretending otherwise. The explanation also points out that the verb already in the sentence gives the answer away.

Two questions use irregular verbs, chosen so that the question tests something: a verb whose past participle is identical to its plain form, and one whose participle differs from its simple past. A regular verb would make both questions trivial, since the two forms would be the same word.

Two more are modifiers attached to the wrong thing — trees that appear to be walking through a park, a computer that appears to have written a report — and the repairs are judged by what comes immediately after the opening phrase, not by whether the sentence sounds better. The rewritings offered include ones that move the phrase elsewhere without solving anything.

The last three cover the pair of words most often confused in each direction: the uncommon verb sense of "effect", which means to put something into force rather than to influence it, and the distinction between what can be counted and what can only be measured. And one question repairs a comparison between a building's architecture and a building, which needs "that of" to compare like with like.

Every person, firm and place is invented, and nothing is drawn from any official publication.

• Find the true subject by crossing out interrupting phrases, and by looking past an inverted word order
• Distinguish "the number of", which is singular, from "a number of", which is not
• Choose the object form of a pronoun after a preposition, including in the phrase people most often get wrong
• Match a pronoun to a singular determiner such as "each", using the verb already in the sentence as evidence
• Use the past participle of an irregular verb correctly after an auxiliary
• Repair a dangling modifier by putting the right noun immediately after the opening phrase
• Use "effect" as a verb meaning to put into force, and "fewer" for things that can be counted
• Compare like with like, using "that of" to stand in for a repeated noun

Written for this catalogue, with no source document. The content is the usage material named in ACT's own public description of the English section — agreement, pronoun case, verb forms, modifier placement and idiom; every sentence, option and explanation here is original, and nothing is reproduced from any ACT publication or released test. Note that questions are deliberately not built on constructions where careful writers disagree, such as singular "they", since those are live arguments rather than settled rules. Zestly is an independent study tool. It is not affiliated with ACT, which owns the test, and it is not an exam centre.