Usage and Mechanics

Grammar, punctuation, and sentence structure for ACT English

Usage and Mechanics (ACT English)

Grammar and Usage

Subject-Verb Agreement

Rule: Singular subjects use singular verbs, plural use plural.

❌ "The box of cookies are here" ✓ "The box of cookies is here" (subject is "box")

Pronoun-Antecedent Agreement

Rule: Pronouns must match their antecedent in number.

❌ "Each student must bring their book" ✓ "Each student must bring his or her book" ✓ "Students must bring their books"

Punctuation

Commas

Use for:

  • Lists: "apples, oranges, and bananas"
  • Before FANBOYS with two complete sentences: "I ran, and she walked"
  • After introductory phrases: "After the game**,** we left"

Semicolons

Use to join two independent clauses: "I love reading**;** she prefers movies"

Sentence Structure

Run-on Sentences

❌ "I studied I passed" → needs punctuation/conjunction ✓ "I studied, and I passed" ✓ "I studied; I passed" ✓ "I studied. I passed"

Fragments

❌ "Because I was tired." → incomplete thought ✓ "I left early because I was tired."

ACT Tips

  • "No change" is often right! Don't overthink
  • Shorter is usually better (if grammatically correct)
  • Trust your ear but verify with rules

📚 Practice Problems

1Problem 1easy

❓ Question:

Which is correct?

A) Each of the students have a book. B) Each of the students has a book.

💡 Show Solution

Solution:

"Each" is the subject (singular). "Of the students" is a prepositional phrase.

Singular subject needs singular verb: has

Answer: B - Each of the students has a book.

ACT Tip: Ignore words between subject and verb when checking agreement!

2Problem 2medium

❓ Question:

Which is correct?

A) I enjoy reading, my sister likes sports. B) I enjoy reading; my sister likes sports. C) I enjoy reading my sister likes sports.

💡 Show Solution

Solution:

Two independent clauses (complete sentences):

  • "I enjoy reading"
  • "My sister likes sports"

Cannot use:

  • C: No punctuation (run-on)
  • A: Comma alone (comma splice)

Must use:

  • Semicolon, period, or comma + conjunction

Answer: B - I enjoy reading; my sister likes sports.

3Problem 3hard

❓ Question:

Which is the BEST revision?

Original: "The team, which practiced every day, they won the championship."

A) NO CHANGE B) The team, which practiced every day, won the championship. C) The team which practiced every day, they won the championship.

💡 Show Solution

Solution:

The original has two subjects: "team" AND "they"

This creates awkward redundancy.

Fix: Remove "they"

A: Keeps the error B: Removes "they" ✓ C: Missing commas around non-essential clause AND keeps "they"

Answer: B

ACT Tip: Avoid redundant subjects!

🎴

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