问题补充:
The construction of the two new railway lines by now.
A. have been completed
B. has been completed
C. has completed
D. have completed
答案:
A. have been completed
(答案→)B. has been completed
C. has completed
D. have completed
解析:考查时态及语态,根据题中的时间by now,应用现在完成时态,句意:到现在为止两条新铁路线的建造已经被完成了。根据语境应用被动语态,所以选B。