There points to a place or starts a sentence (there is/are); their shows possession; they're always expands to they are—on ACT English, test which job the word must do before you look at the choices. Same pattern as your/you're and who's/whose.
Three jobs, three spellings
- there: location or existential opener— There are three options.
- their: belonging to them— their research continued.
- they're: they are— They're planning a follow-up study.
Apostrophe overview: apostrophes on ACT English.
How to decide fast
- Try they are in place of the underlined word. If it works, choose they're.
- If the next word is a noun, test their (possession).
- If the sentence needs a place or there is/are, use there.
Bonus pairs the ACT reuses
- your vs you're: possession vs you are
- whose vs who's: possession vs who is / who has— see relative pronouns
- its vs it's: its vs it's on ACT English
Common wrong answers
All three homophones appear as swaps in otherwise identical choices. Read the sentence aloud with your pick—if grammar breaks, eliminate. Log these in common ACT English mistakes.
Drill
Write five sentences using each form correctly, then mix ACT-style underlines and test alternatives. Broader grammar hub: ACT English grammar rules.
Start practicing
Start with a free diagnostic, then drill your weak spots with 15-question quizzes and track how you're doing across Reading, English, and Math. Compare plans whenever you're ready to go further.
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