ACT English Grammar Essentials

Vocabulary flashcards covering essential ACT English grammar topics such as sentence structure, agreement, punctuation, and style.

Sentence

A group of words that expresses a complete thought and contains both a subject and a predicate.

Sentence Fragment

An incomplete thought that is missing a subject, a predicate, or both.

Subject

The noun or pronoun in a sentence that performs the action or is described.

Predicate

The part of a sentence that contains the verb and tells something about the subject.

Number Agreement

The rule that subjects and verbs (and pronouns with antecedents) must both be singular or both be plural.

Prepositional Phrase

A phrase beginning with a preposition (e.g., in, of, for) that often separates a subject from its verb and can hide the true subject.

Collective Noun

A singular noun that names a group (e.g., team, class) and takes a singular verb.

Collective Pronoun

Words like everyone, each, somebody that refer to many items but are grammatically singular.

Comma

Punctuation used to separate items in a list, after introductory elements, or to set off non-essential information.

Semicolon

Punctuation that links two closely related independent clauses or separates items in a complex list.

Colon

Punctuation used after a complete sentence to introduce a list, explanation, or clarification.

Dash

Punctuation that creates an emphatic break, interruption, or added emphasis within a sentence.

Apostrophe

A punctuation mark used to show possession or form contractions, never to make nouns plural.

Parentheses

Punctuation that encloses extra, non-essential information that can be removed without affecting grammar.

Parallelism

Keeping grammatical structures consistent within a list or paired ideas to create flow and balance.

Transition Word

A connecting word or phrase (e.g., however, moreover, because) that shows relationships between ideas.

Wordiness

Using more words than necessary; concise wording is preferred on the ACT.

Word Order

The logical sequence of words in a sentence; misplaced words can create confusion.

Illogical Comparison

A faulty comparison in which items of different types or groups are compared incorrectly (e.g., car vs. Mike).

Proper Wording

Choosing the correct word among commonly confused pairs (e.g., accept vs. except; its vs. it's).

Verb Tense

The form of a verb that shows time: past, present, or future; must remain consistent unless reason to shift.

Singular Possessive Apostrophe

Place the apostrophe before the s (dog’s leash) to show one owner.

Plural Possessive Apostrophe

Place the apostrophe after the s if the plural ends in s (dogs’ leashes); add ’s if the plural does not end in s (children’s toys).

“Cut Out the Middle Man”

Editing trick of removing interrupting phrases to match the subject directly with the verb for agreement checks.

Pronoun-Antecedent Agreement

Pronouns must match their antecedents in number and gender (one … one’s, they … their).

“I” vs. “Me”

Use I as a subject and me as an object; test by removing the other nouns/pronouns in the phrase.

Adjective

A word that describes a noun (good, smart, tall).

Adverb

A word that describes a verb, adjective, or other adverb, often ending in -ly (well, quietly).

‘BUT’ Transition Family

Contrast connectors: however, yet, nevertheless, despite, in contrast, instead.

‘ALSO’ Transition Family

Addition connectors: additionally, moreover, furthermore, likewise, as well.

‘BECAUSE’ Transition Family

Cause-and-effect connectors: because, since, as, due to, therefore, consequently.

Colon for List Rule

A complete independent clause must precede the colon that introduces a list or explanation.

Dash Flexibility

Dashes can replace commas, colons, or parentheses for emphasis but should be used sparingly and consistently.

Concise Revision Example

Wordy: The jury has come to a decision and chosen what it thinks. Concise: The jury has reached a decision.

Illogical Comparison Fix

Wrong: John’s car is nicer than Mike. Right: John’s car is nicer than Mike’s car.