Topic 6Conventions of Standard English

Punctuation

ACT punctuation questions are really sentence-structure questions with marks attached.

Core Idea

Pick the mark that fits the grammar around it. A comma, semicolon, colon, dash, or apostrophe is correct only when the surrounding words make that mark legal.

Understanding

Rule: Before choosing punctuation, decide what the sentence parts are doing. Are you separating an intro, setting off extra information, joining two full clauses, or introducing a list or explanation?

  • If the punctuation changes the grammar, it changes the answer. ACT rewards the choice that leaves the sentence clean and complete, not the choice with the fanciest mark.
Question

Worked Example

Which choice best completes the sentence?

"The old theater finally reopened after months of repairs _____ the first performance sold out in two days."

Select an answer to see the explanation

Concept Guides

8
1

Use commas to separate introductory elements, nonessential clauses, and items in a series.

2

Use commas with coordinating conjunctions to join independent clauses.

3

Use semicolons to join closely related independent clauses; use with conjunctive adverbs when appropriate.

4

Use colons to introduce lists or explanations when grammatically valid.

5

Use dashes/parentheses for parenthetical information without breaking grammar.

6

Use apostrophes for possession and contractions; avoid apostrophes in plurals.

7

Use quotation marks and punctuation placement appropriately in dialogue/quoted material.

8

Avoid unnecessary punctuation that splits subject–verb or verb–object pairs.