16. We haven’t settled the question _________ it is necessary for him to study abroad.
A. if B. where C. whether D. that
【答案】C。解析：考查同位语从句。句意：我们还没有解决他是否有必要去国外学习的问题。：C 题干中it is necessary for him to study abroad是解释question的内容，是一个同位语从句;句意表达的是还为不确定的内容，要用表示是否的whether来连接。If也有是否的意思，但不能引导表语从句。因此C为正确答案。
17. I went to the school _________ my father once worked.
A. that B. which C. where D. on which
【答案】C。解析：此句先行词the school，定语从句my father once worked，二者构成的完整句为My father once worked in the school. in the school可以用固定关系引导词中的地点关系引导词where表示，也可以用介词+关系代词in which表示。故选C。
18. She had golden hair when she was a child, but _________ she got older and older, her hair went darker and darker.
A. while B. when C. after D. as
【答案】D。解析：as 引导的时间状语从句，更突出强调“随着”“一边……边……”，如用when或while 则无此效果。故选D。
19. Without his wartime experiences, Hemingway_________ his famous novel A Farewell to Arms.
A. Didn’t write B. hadn’t written C. wouldn’t write D. wouldn’t have written
【答案】D。解析：解题时考生需要理解题干中暗含的条件，相当于if引导的虚拟条件从句，所以其主句的谓语动词则用相应的形式。根据语境without his wartime experiences“没有他战时的经历”，可知是对过去情况的否定虚拟，所以主句的谓语动词需would/could/might/should have done，故选D。
20. —How was the televised debate last night?
—Super! Rarely_________ so much media attention.
A. a debate attracted B. did a debate attract
C. a debate did attract D. attracted a debate