问题补充:
— Flight MU257 , I must be off now.
— Have a nice trip.
A. is being announced
B. has announced
C. was announcing
D. had been announced.
答案:
(答案→)A. is being announced
B. has announced
C. was announcing
D. had been announced.
解析:本题考查时态。根据语境I must be off now 可知,MU257航班正在被播报,故用现在进行时的被动语态,故选A。