THEY HAD TO WAIT FOR TWELVE HOURS BEFORE THEIR FLIGHT LEFT.A. ONLY A...

Câu 36: They had to wait for twelve hours before their flight left.

A. Only after they had waited for twelve hours did their flight leave.

B. Not until they had to wait for twelve hours did their flight leave.

C. Did they have to wait for twelve hours when their flight left.

D. Only when they waited for twelve hours then their flight left.