Faulty parallelism in sentences occurs when what?

• A. Sentences need to have the same length
• B. Phrases need to have the same verb form
• C. Subject agreement is optional
• D. Pronouns must be clear

Answer: (B)

Faulty parallelism happens when the parts of a sentence that should mirror each other don’t share the same form. When you join actions or ideas in a list or in paired phrases, each item should follow the same grammatical pattern so the sentence reads smoothly and clearly. That’s why keeping the same verb form across the items is important: it creates a balanced, easy-to-follow rhythm. If you mix different forms—say one item is an infinitive and another is a gerund—the sentence sounds off and can confuse who is doing what. For example, using a consistent pattern like swim, run, and bike (all in the same form) versus mixing forms in a list leads to clearer meaning and better flow. The other choices miss the structural issue at the heart of parallelism, since they’re about length, pronoun clarity, or general agreement rather than keeping the parallel elements in the same form.