Key Grammar Rules and ACT English Strategies

Subject-Verb Agreement

A singular subject takes a singular verb, and a plural subject takes a plural verb. Ignore phrases between the subject and verb.

Pronoun-Antecedent Agreement

A pronoun must agree in number and gender with its antecedent. (Ex: Everyone his or her book, not their book.)

Who vs. Whom

Who = subject (he/she/they). Whom = object (him/her/them). Tip: If you can replace it with he/she, use who. If you can replace it with him/her, use whom.

Its vs. It's

Its = possessive (The dog wagged its tail). It's = contraction for it is (It's raining).

There vs. Their vs. They're

There = location (over there). Their = possessive (their house). They're = contraction of they are (They're coming).

Affect vs. Effect

Affect = verb (influence). Effect = noun (result). (Ex: The weather affects my mood. The new rule had a big effect.)

Comma Before a Conjunction in a Compound Sentence

Use a comma before and, but, or, nor, for, so, yet when joining two independent clauses. (Ex: I studied, but I still felt nervous.)

No Comma Between an Independent and Dependent Clause

Do not place a comma before because, since, when, after, if, etc., if the second clause is dependent. (Ex: I left because I was tired.)

Commas in a List

Use commas to separate items in a list, including before and/or (Oxford comma). (Ex: I bought apples, oranges, and bananas.)

Dashes (—)

Used for emphasis or to set off extra information, like parentheses. (Ex: My brother—who loves soccer—plays every weekend.)

Colons (:)

Used before a list, explanation, or example. The first clause must be independent. (Ex: There was only one option: leave immediately.)

Semicolons (;)

Used to join two independent clauses without a conjunction. (Ex: I love math; it's my best subject.)

Apostrophes in Possession

• Singular: Add 's (The cat's toy). • Plural: Add s' (The cats' toys). • Irregular plural: Add 's (The children's books).

Misplaced Modifiers

A phrase should be next to what it describes. (Incorrect: Running to school, the bus left without me. Correct: Running to school, I saw the bus leave.)

Parallel Structure

Items in a list or comparison should match in form. (Incorrect: I like to run, swimming, and to bike. Correct: I like running, swimming, and biking.)

Redundancy

Avoid unnecessary repetition. (Incorrect: Free gift. Correct: Gift.)

Wordiness

The most concise option is usually correct. (Incorrect: The reason why is that he was late. Correct: He was late.)

Transition Words

• Addition: furthermore, moreover, in addition • Contrast: however, on the other hand, nevertheless • Cause & Effect: therefore, thus, consequently

Commonly Confused Words

Ensure proper word choice (e.g., then vs. than, accept vs. except).

Main Idea Questions

Look at the topic sentence and concluding sentence to determine the passage's main idea.

Adding/Deleting Sentences

Keep a sentence if it adds relevant information and delete if it is off-topic or redundant.

Best Conclusion

A conclusion should reflect the main point of the passage. Look at the thesis!

Sentence Placement

A sentence should be placed where it logically flows and connects to surrounding sentences.

Conciseness Questions

The shortest answer that retains clarity and meaning is usually correct.

Tone & Style

The tone should match the passage (avoid overly formal or casual choices unless the passage justifies it).

Read the Full Sentence

Don't just read the underlined portion—read the whole sentence to ensure it makes sense.

Skip the Answers First

Read the question before looking at the answer choices to predict the right answer.

Plug in the Answers

Try each option in the sentence and see which sounds best.

Beware of No Change Options

Only pick NO CHANGE if you're sure the sentence is already correct.

Eliminate Wrong Answers First

If an answer is wordy, off-topic, or grammatically incorrect, eliminate it immediately.

Don't Overthink It

The simplest, most logical answer is usually right.