Hard ACT Grammar Practice Questions

Concept Explanation

Hard ACT grammar questions involve complex sentence structures, subtle punctuation rules, and sophisticated rhetorical choices that test a student's ability to maintain logical consistency and stylistic clarity. While many students are familiar with basic subject-verb agreement or comma usage, the most difficult questions on the ACT Prep English section often focus on misplaced modifiers, restrictive versus non-restrictive clauses, and the nuances of semicolons and colons. According to the official ACT guidelines, these high-level questions require an understanding of how individual grammatical components function within the context of an entire paragraph. Success on these items depends on recognizing when a sentence is technically correct but rhetorically weak, or when a seemingly correct punctuation mark creates a run-on sentence. To excel, students should review specific ACT English practice questions that emphasize these advanced mechanical errors.

Solved Examples

1. Example: Misplaced Modifiers
   Sentence: Running toward the finish line, the trophy was already being polished by the officials.
   Solution:

   1. Identify the participial phrase: "Running toward the finish line."

   2. Determine the logical subject: Who is running? The officials or an athlete (implied)? It is certainly not the trophy.

   3. Check for dangling modifiers: The current structure implies the trophy is running.

   4. Correction: "Running toward the finish line, the athlete saw the officials polishing the trophy."

2. Example: Restrictive vs. Non-restrictive Clauses
   Sentence: My brother, who lives in Chicago, is a doctor, but my brother who lives in New York is a lawyer.
   Solution:

   1. Identify the clauses: "who lives in Chicago" and "who lives in New York."

   2. Determine if the information is essential (restrictive) or extra (non-restrictive).

   3. If the speaker has multiple brothers, the location is essential to identify which brother is being discussed.

   4. Correction: "My brother who lives in Chicago is a doctor, but my brother who lives in New York is a lawyer." (No commas needed for restrictive clauses).

3. Example: Semicolon and Conjunctive Adverbs
   Sentence: The research team found no evidence of water on the planet, however, they decided to continue the mission.
   Solution:

   1. Determine if there are two independent clauses. Clause 1: "The research team... planet." Clause 2: "they decided... mission."

   2. Identify the transition word: "however."

   3. Apply the rule: A comma cannot separate two independent clauses joined by a conjunctive adverb (comma splice).

   4. Correction: "The research team found no evidence of water on the planet; however, they decided to continue the mission." Use a semicolon before "however" and a comma after.

Practice Questions

1. The committee members, having deliberated for several hours, finally reaching a consensus regarding the new zoning laws.

A. NO CHANGE
B. hours; finally reaching
C. hours, finally reached
D. hours finally reached,

2. Each of the participants in the grueling marathon were required to undergo a medical examination before the race began.

A. NO CHANGE
B. was required
C. have been required
D. are required

3. The ancient ruins of the temple, which were discovered by a team of archaeologists in the early 1920s, remains one of the most significant historical sites in the region.

A. NO CHANGE
B. remaining
C. has remained
D. remain

4. Neither the lead singer nor the backup guitarists was prepared for the sudden power outage during the encore.

A. NO CHANGE
B. were prepared
C. is prepared
D. has been prepared

5. While the novel was praised for its intricate plot; its character development was criticized as being somewhat superficial.

A. NO CHANGE
B. plot, its
C. plot. Its
D. plot: its

6. The sophisticated software allowed the engineers to simulate the bridge's structural integrity, this saved the company thousands of dollars in physical testing.

A. NO CHANGE
B. integrity; which saved
C. integrity, which saved
D. integrity, saving;

7. Although the CEO's speech was brief, but it effectively addressed the concerns of the shareholders regarding the recent merger.

A. NO CHANGE
B. brief, yet it
C. brief; it
D. brief, it

8. The scientist's findings were more comprehensive than the previous study, which had relied on a much smaller sample size.

A. NO CHANGE
B. than those of the previous study
C. than the previous studies findings
D. than the study that came before

9. To ensure the safety of the hikers, the park rangers closed the trail, because of the recent heavy rainfall and subsequent mudslides.

A. NO CHANGE
B. trail; because of
C. trail because of
D. trail: because of

10. The museum's collection includes several artifacts from the Ming Dynasty, such as: porcelain vases, silk tapestries, and jade carvings.

A. NO CHANGE
B. Dynasty, such as
C. Dynasty; such as
D. Dynasty such as,

Answers & Explanations

1. Answer: C. The original sentence is a fragment because "reaching" is a participle, not a finite verb. Choice C provides the past tense verb "reached" to complete the independent clause. Reviewing ACT sentence structure practice questions can help identify these fragment errors.

2. Answer: B. The subject of the sentence is "Each," which is a singular indefinite pronoun. Therefore, the verb must be the singular "was required." The phrase "of the participants" is a prepositional phrase that does not affect the number of the verb.

3. Answer: D. The subject is "ruins," which is plural. The non-restrictive clause "which were discovered... 1920s" should be ignored when determining subject-verb agreement. The plural subject "ruins" requires the plural verb "remain." For more on this, check ACT subject-verb agreement practice questions.

4. Answer: B. In a "neither/nor" construction, the verb must agree with the noun closest to it. "Guitarists" is plural, so the verb must be the plural "were prepared."

5. Answer: B. The first part of the sentence is a dependent clause starting with the subordinating conjunction "While." A comma, not a semicolon, must be used to separate a dependent clause from the independent clause that follows. See ACT comma practice questions for similar examples.

6. Answer: C. The original sentence is a comma splice. Choice C uses a relative clause ("which saved...") to correctly modify the preceding idea without creating a new independent clause.

7. Answer: D. Using both "Although" and "but" is redundant. You only need one conjunction to show the relationship between the clauses. Choice D correctly uses "Although" at the start and a comma to separate the clauses.

8. Answer: B. This is an error in logical comparison. You cannot compare "findings" to a "study." You must compare "findings" to the "findings" (those) of the previous study. This is a common trap in ACT grammar practice questions.

9. Answer: C. A comma is generally not used before a prepositional phrase or a dependent clause that follows an independent clause unless it is for clarity or emphasis. In this case, "because of" is essential and should not be preceded by a comma.

10. Answer: B. You should never use a colon after the phrase "such as" or "including." A colon should only follow a complete independent clause. Choice B correctly uses a comma to introduce the list.

1. Which of the following correctly uses a semicolon to join two independent clauses?

• AThe rain fell heavily; and the streets flooded quickly.
• BThe rain fell heavily; the streets flooded quickly.
• CBecause the rain fell heavily; the streets flooded quickly.
• DThe rain fell heavily; flooding the streets quickly.

Frequently Asked Questions

How does the ACT test punctuation?

The ACT focuses on the functional use of commas, semicolons, colons, and dashes to clarify sentence structure and eliminate ambiguity. It specifically tests your ability to avoid comma splices, correctly set off parenthetical information, and manage lists or introductory phrases. You can practice these skills using the AI Question Generator to create targeted drills.

What is the most common grammar error on the ACT?

Comma usage is arguably the most frequent error, particularly regarding non-essential clauses and comma splices. Students often struggle with whether to include commas around a name or a descriptive phrase, which hinges on whether the information is restrictive or non-restrictive. Understanding these rules is vital for a high score on the English section.

Are there specific rules for dashes on the ACT?

Dashes are used on the ACT primarily to set off an emphatic parenthetical phrase or to provide a sudden break in thought. If a pair of dashes is used to interrupt a sentence, they must be used consistently; you cannot start with a dash and end with a comma. They can also function similarly to a colon to introduce an explanation or a list at the end of a sentence.

How can I tell the difference between 'its' and 'it\'s'?

"Its" is a possessive pronoun indicating ownership, while "it's" is a contraction for "it is" or "it has." On the ACT, this is a common diction trap that requires careful reading of the sentence context to determine if a verb is needed. For more practice on confusing words, see ACT diction practice questions.

Why is subject-verb agreement difficult on the ACT?

The ACT often separates the subject from the verb with long prepositional phrases, appositives, or relative clauses to distract the reader. This creates a distance that makes it harder to identify the true subject, leading students to match the verb with the nearest noun instead of the correct one. Consistently identifying the simple subject is the best strategy to avoid this error.

Practice smarter, not harder.

Generate unlimited ACT questions, track your progress, and focus on the topics that need the most work.

Generate ACT Questions