ACT (Enhanced)EnglishMedium

A student is writing an essay and wants to avoid common grammatical errors. They have written the following sentence: "The primary goal of the project was to identify the root causes of customer dissatisfaction, and to implement effective solutions." Which grammatical principle is violated in this sentence?

  1. ASubject-verb agreement
  2. BParallel structure
  3. CDangling modifier
  4. DPronoun-antecedent agreement
Show answer & explanation

Correct answer: B. Parallel structure

The sentence lists two items that are part of the 'primary goal': 'to identify' and 'to implement.' Both should be presented in a grammatically similar form. The inclusion of 'and' but then repeating 'to' before 'implement' creates a slight break in parallel structure. The 'to' is redundant and breaks the parallelism. The sentence should ideally be 'to identify... and implement...'.

Why the other options are wrong

  • A. Subject-verb agreement is correct; 'goal' (singular) matches 'was' (singular).
  • C. There is no introductory phrase that could be misinterpreted as a dangling modifier.
  • D. There are no pronouns in the sentence that violate pronoun-antecedent agreement.

Parallel Structure (Parallelism)

Parallel structure (or parallelism) is the repetition of a chosen grammatical form within a sentence or across sentences. By making sure all items in a list or series, or elements in a comparison, have the same grammatical structure, writers create balance, rhythm, and clarity.

  • Applies to words, phrases, or clauses in a series.
  • Ensures elements are grammatically similar (e.g., all nouns, all verbs, all infinitives).
  • Enhances readability, clarity, and rhetorical effect.
  • Commonly seen in lists, comparisons, and correlative conjunctions (e.g., 'either/or').

Memory trick: Grammar builds strong sentences; structure gives them form.

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