But for these interruptions the meeting half an hour ago.A. was finishedB. would have fin

问题补充：

But for these interruptions, the meeting half an hour ago.

A. was finished

B. would have finished

C. had finished

D. would finish

答案：

A. was finished

(答案→)B. would have finished

C. had finished

D. would finish

解析：本句是一个含蓄的虚拟语气，but for…要不是，如果没有…；句意：要不是这些打扰，这个会议半小时前就结束了。根据句意说明对会议产生的打扰是过去发生的事情，故使用would have done对过去的情况进行虚拟。故B正确。