Grammar

Parallel Structure

Parallel structure (or parallelism) means using the same grammatical pattern for similar elements in a sentence. It creates rhythm and clarity.

The Rule

Elements that are alike in function should be alike in construction.

Examples

Not ParallelParallel
She likes reading, to write, and swimming.She likes reading, writing, and swimming.
The study was quick, efficient, and cost little.The study was quick, efficient, and inexpensive.
He promised to work harder and that he would arrive early.He promised to work harder and to arrive early.

Common Patterns

Lists: Use the same form for all items.

  • ❌ "The course covers writing, how to research, and citations."
  • ✓ "The course covers writing, researching, and citing."

Comparisons: Match the structure on both sides.

  • ❌ "Writing is harder than to speak."
  • ✓ "Writing is harder than speaking."

Pairs with correlatives (both/and, either/or, not only/but also):

  • ❌ "She not only writes essays but also is editing papers."
  • ✓ "She not only writes essays but also edits papers."

Parallel structure makes your writing more readable and professional.

Quick Tip

When you have a list or comparison, check that each element follows the same grammatical pattern.