Question

【題目】By the time I got to the airport，the plane ________ .

A. have taken off B. had taken off

C. is taken off D. is taking off

Answer 1

【答案】B

【解析】

句意：等我到機(jī)場的時(shí)候，飛機(jī)已經(jīng)起飛了。have taken off已經(jīng)起飛了，是現(xiàn)在完成時(shí)態(tài)；had taken off過去完成時(shí)態(tài)；is taken off被起飛了，是一般現(xiàn)在時(shí)的被動語態(tài)；is taking off將要起飛，現(xiàn)在進(jìn)行時(shí)表示將來。句中by the time引導(dǎo)的是狀語從句，從句用一般過去時(shí)態(tài)，主句用過去完成時(shí)態(tài)，故選B。