19 ACT Grammar Rules

ACT Grammar Rule #9: A Pronoun Must Always Match its Antecedent.

Antecedent: the word a pronoun refers to. Incorrect: We went to the store this morning and they were out of milk. Correct: We went to the store this morning and it was out of milk.

ACT Grammar Rule #5: English Has Six Basic Tenses.

Being familiar with the general structures of verb tenses will give you an edge on the exam. Simple past, simple present, simple future. Past perfect, present perfect, future perfect (has have had).

ACT Grammar Rule #6: English Has Six Progressive Tenses.

Describe continuous actions that happen in the past, present, or future. Like basic tenses, they also have simple and perfect aspects. Examples: was watching, am studying, will be doing.

ACT Grammar Rule #11: Coordinating Conjunctions Join Clauses That Are Equally Important.

FANBOYS: For And Nor But Or Yet So

ACT Grammar Rule #14: Make Sure the Right Things Are Being Compared in a Sentence.

Incorrect: Danny's test scores weren't as good as Bryan. Correct: Danny's test scores weren't as good as Bryan's (test) scores.

ACT Grammar Rule #16: Misplaced Modifiers Describe the Wrong Part of the Sentence.

Incorrect: I don't get my sister can walk our dog in heels.

ACT Grammar Rule #15: Isolate Each Phrase in Prepositional Phrases to Ensure Parallelism.

Incorrect: I was both surprised and worried about the outcome of our class elections. Correct: I was both surprised BY and worried about the outcome of our class elections.

ACT Grammar Rule #10: Watch Out for Ambiguous Pronouns.

Incorrect: Mark met Steve after he had dinner. Correct: Mark met Steve after Mark had dinner.

ACT Grammar Rule #17: Dangling Modifiers Don't Actually Modify Anything in The Sentence.

Incorrect: Shoving food into my mouth, a content sigh escaped me. Correct: Shoving food into my mouth, I sighed contentedly.

ACT Grammar Rule #19: Essential Appositives Are Not Set Off with Commas.

NOTHING

ACT Grammar Rule #1: A Complete Sentence Needs a Subject and a Predicate.

One of our biggest ACT grammar tips is to watch out for fragments that seem to be connected to the previous sentence, but can't stand alone grammatically. For example: She was a wonderful professor. The most wonderful professor. The second sentence does not have a subject or a complete predicate. An acceptable edit of the sentence would be: She was a wonderful professor. In fact, she was the most wonderful professor.

ACT Grammar Rule #2: A Comma Splice Improperly Combines One or More Independent Clauses.

Students frequently make the mistake of attempting to combine run-on sentences with a comma, and this results in a grammatical error known as the comma splice. Example: I run five miles along the river on Saturdays, I do this even when it's raining.

ACT Grammar Rule #7: Watch Out for Subjects that Come After the Verb.

Subject-verb agreement questions on the ACT also try to confuse you with sentences in which the subject comes after the verb. This is called subject-verb inversion. For example, in the sentence... Under the lamppost stood a mysterious man. (No comma).

ACT Grammar Rule #8: Verb Tenses in a Passage Should Be Consistent.

The verb you choose to change depends on the greater context in the passage.

ACT Grammar Rule #12: Subordinating Conjunctions Join Clauses Where One Clause is the Most Important.

There are many subordinating conjunctions. Here are a few common ones: after, although, because, if, than, that, when, where, while, before, as soon as, since, though, unless, until, once.

ACT Grammar Rule #13: Make Sure That All Items in a List Are Equal.

To escape the wicked witch, the boy ran out of the gingerbread house, rolled down the hill, and jumped across a river of fire.

ACT Grammar Rule #4: Modals Are Helping Verbs that Define the Mood of Regular Verbs.

Verbs change to their bare form following modals, meaning that there are no tense or subject-verb agreement markers. ACT English often tests these kinds of minor shifts in verb form, so be on the lookout. Examples: She is → She should be. They are → They could be. He eats → He might eat.

ACT Grammar Rule #3: Check for Subject Verb Agreement for Present Tense and "To Be" Verbs.

When you come across a question that seems to be testing subject-verb agreement, identify the subject right away and match it with the verb.

ACT Grammar Rule #18: Most of the Time, Appositives Are Set Off with Commas.

You can lift whatever is set off with commas out of the sentence, and it should still read as a sentence.