IMO Practice Test — Past Perfect & Future Perfect

8 Questions • 15 min • Olympiad level

15:00
Question 1 of 8
Spot the error: 'No sooner had the bell rung than the students have left.'
have left → had left
had rung is wrong
than is wrong
no error
Explanation: Both clauses are past; the later needs the past tense: 'than the students left' (or 'had left' is replaced by simple past). Standard form: 'No sooner had the bell rung than the students left.'