Question

【题目】The manager __________ the workers how to improve the program since 9 am.

A. has told B. is telling

C. has been telling D. will have told

Answer 1

【答案】C

【解析】句意：自从上午九点，经理一直在告诉工人们如何去改善这个程序。根据since 9 am可知设空处应该用现在完成时，故排除B、D两项。又根据语境可知设空处强调动作现在还在进行，故答案为C项。