1. I have never been to London, but that is the city ______. (1997)
A. where I like to visit most B. I’d most like to visit
C. which I like to visit mostly D. where I’d like most to visit
B, 首先排除A，因为the city在从句中作宾语，不能用where引导;C中mostly表示“通常，大部分”，意思不通顺;表示“最想”，用most like,不是like most, most是much的最高级，much一般不修饰不定式，多用于修饰分词。He was much pleased.
2. She remembered several occasions in the past ___ she had experienced a similar feeling. (98)
A. which B. before C. that D. when
D，从句有自己的主语和宾语，因此不选AC，when引导定语从句在句中作时间状语。B项不合语法，因为主句的时态是一般过去时，从句却是过去完成时。
3. I’ve never been to Lhasa, but that’s the city ______. (1999)
A. I’d most like to visit B. which I like to visit mostly
C. where I like to visit D. I’d like much to visit
A。
4. Firms that use computers have found that the number of staff ______ is needed for quality control can be substantially reduced. (2000)
A. whose B. as C. what D. that
D，that在从句中作主语。使用电脑操作的工厂已经发现可以大大减少质检员工的数量。
5. We’ve just installed two air-conditioners in our apartment, ______ should make great differences in our life next summer. (2002)
A. which B. what C. that D. they
A，指代前面的整个句子。
6. They overcame all the difficulties and completed the project two months ahead of time, ______ is something we had not expected. (2003)
A. which B. it C. that D. what
A，同上。“他们克服一切困难，提前两个月完成了工程，这是我们没有料到的事。”
7. We can assign the task to ______ is capable and trustworthy. (1994)
A. whomever B. who C. whom D. whoever
D，介词to后面是个宾语从句，从句缺主语;whom和whomever虽然可以接宾语从句，但它们不能在从句中作主语，AC不对;whoever语义比who强烈，更贴切。
8. The team can handle whatever _____. (1997)
A. that needs handling B. which needs handling
C. it needs handling D. needs to be handled
D，whatever引导的分句作handle的宾语，又在从句中作主语，因此不需要再加任何其他主语，ABC都有多余的主语成分。
9. After __ seemed an endless wait, it was her turn to enter the personnel manager’s office. (99)
A. that B. there C. what D. it
C，after在句中时介词还是连词?如果是连词，从句中的时态通常为完成体，所以排除连词的可能性。既然after是介词，那么后面必定是宾语从句，后面的从句缺主语，只有what既引导宾语从句，又在宾语从句中作主语;BD都不能引导宾语从句。A虽然可以引导宾语从句，但不在从句中充当任何语法成分。
10. Have you ever been in a situation _____ you know the other person is right yet you cannot agree with him? (2002)
A. by which B. that C. in where D. where
B，situation后的从句是对situation作出具体的解释，因此是同位语从句。
