Question

15. They did everything in their power to save the building dating back to the Qing Dynasty, but their efforts were     .

A. in turn       B.  in time

C. in vain         D.  in need

Answer 1

15. C考查介词短语辨析。句意：他们在能力范围内尽一切努力去挽救始于清朝时期的建筑，但是他们的努力是徒劳的。in turn轮流；in time及时；in vain徒劳；in need需要。根据but可知后面和前面内容是转折关系，选C。