1.Shirley _______ a book about China last year but I don't know whether she has finished it.
A.has written
B.wrote
C.had written
D.was writing
2. Sorry, I'm late.I _____have turned off the alarm clock and gone back to sleep again.
A.might
B.should
C.can
D.will
3. What would have happened _______, as far as the river bank
A.Bob had walked farther
B.if Bob should walk farther
C.had Bob walked farther
D.if Bob walked farther
1. 正确答案：D
解析：所提供的情景but I don't know whether she has finished it表明当时她正在写这本书,但是不知道是否完成,要用过去进行时态.时间状语last year对作出正确选择起到很大的干扰作用.
2. 正确答案：A
解析：might have done sth.(过去)可能做某事,should have done sth.本不应该做某事.所提供的
情境I'm late.表明说话人可能把闹钟关上了,而不是本来不应该把闹钟关上而关上了.
3. 正确答案：C
解析：根据主句的谓语动词would have happened,可以断定要用虚拟语气中.当条件状语从句中的if省略时,要倒装.如果鲍勃走得远一点,走到岸边,会发生什么事呢
4. No one has _____ been able to trace the author of the poem.
A. still
B. yet
C. already
D. just
5. Our research has focused on a drug which is so _____ as to be able to change brain chemistry.
A. powerful
B. influential
C. monstrous
D. vigorous
6. We had a party last weekend, and it was a lot of fun. So let’s have ______ one this weekend.
A. another
B. more
C. the other
D. other
4、 正确答案：B
解析：yet 常用于现在完成时的否定句中, 意为“尚, 还”。
5. 正确答案：A
解析：powerful (=having or producing great power) 强有力的。在这里四个形容词中, 只
有powerful (有效力的) 可与表示药物的名词搭配。influential 有影响的, 有势力的, monstrous 异常大的, vigorous 精力旺盛的, 强健有力的。
6、 正确答案：A
解析：another 可以说是再一次的意思，more 、other显然不合题意，the other 通常指两者中的另外一个。
