Question

— Would you please tell me _________?
— In half an hour

1. A.
   when the plane left
2. B.
   when the plane will leave
3. C.
   when will the plane leave

Answer 1

B
此题考查宾语从句的语序和时态。宾语从句必须是陈述句语序，时态前后保持一致。根据答语In half an hour.一小时后，可知上文描述的是将来的动作，要用将来时。故选B。