Reading & WritingExpression of IdeasMedium frequency

SAT Reading & Writing: Parallel Structure in Compound Sentences

25+ practice questions in Praczo

What you need to know

The concept, explained

  • 1

    When linking two clauses with correlative conjunctions (Either/Or, Neither/Nor, Not only/But also), the grammatical structures following each half MUST match.

  • 2

    If you say "Either TO stay OR TO go" (infinitive/infinitive) it is parallel.

  • 3

    If you say "Either TO stay OR going" (infinitive/gerund) it is flawed and incorrect.

Common mistakes
  • Ignoring the structure and picking a choice based entirely on how "conversational" it sounds.
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The new software update is designed not only to improve battery life but also _____

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