11.He was busily engaged ______ writing letters. 【 B 】
A. on
B. in
C. with
D. by
【答案解析】：be engaged in：从事，忙于。
12.Do remember to ______ the light when you leave the room. 【 C 】
A. turn up
B. turn on
C. turn off
D. turn down
【答案解析】：根据句意，应该选择“关闭”。句意：离开房间时一定记着把灯关掉。
13.The atmosphere consists of an ocean of gases ______ miles high. 【 B 】
A. hundreds
B. hundreds of
C. of hundreds
D. of hundreds of
【答案解析】：译文：大气由上百英里高的气体组成。“hundred，thousand等数词的复数形式+of短语”表示的是不确切的数量。
14.Not only the students but also the old teacher ______ been changed. 【 C 】
A. was
B. were
C. has
D. have
【答案解析】：not only…but also…是固定搭配，意思是：不但……而且……。它需要遵循就近原则，谓语动词应与the old teacher一致，所以答案是C.
15.—— ________ I had!
—— You really suffered a lot. 【 A 】
A. What a time
B. What time
C. How a time
D. how time
【答案解析】：感叹句分两类：
1.What + n.+主谓部分2.How + adj. / adv. / v.+主谓部分。本题属第一种，但省略了bad，相当于 What a bad time I had! 这是个习惯用语。
16.The advertisements are trying ________ people to buy things they don‘t really need.【 D 】
A. persuade
B. persuading
C. be persuading
D. to persuade
【答案解析】：try to do：试图做某事。
17.Practice ________ English every day. 【 D 】
A. speak
B. to speak
C. speaks
D. speaking
【答案解析】：本题考查的是practice后面要跟动词的ing形式。
18.The discount houses were first established in that period of time ________ people‘s purchasing power was low. 【 C 】
A. which
B. that
C. when
D. where
【答案解析】：先行词是in that period of time，所以关系词应选择when.
19.Please write a report ________ the above subjects are to be covered. 【 B 】
A. which
B. in which
C. that
D. in that
【答案解析】：in which the above subjects are to be covered是report的定语从句。which指代先行词report，in用于与report搭配。
20.The reason ________ I‘m writing is to ask for your permission to translate your latest novel into Chinese. 【B 】
A. because
B. why
C. for
D. as
【答案解析】：本题考查的是定语从句的用法。先行词是the reason;引导词why表示原因。
