通常使用非限制性定语从句的情形 1．当先行词表示的是世界上独一无二的人或物时。   The sun, which gives us light and heat, is a fixed star.   太阳是一颗恒星，它给我们光和热。   Last year I visted the People's Great Hall, where many important meetings are held every year.    去年我参观了人民大会堂，每年许多重要会议都要在那里举行。 2．当定语从句修饰整个主句时。   Taiwan belongs to China, as everyone knows.   众所周知，台湾属于中国的领土。   The weather was very terrible, which we hadn't expected.    天气非常糟糕，这点们没有料到。 不知不觉背单词 随时随地背单词 新概念英语青少版 3．当先行词是专有名词，或先行词本身指示意义十分明确时。    Mr. Joe lives in Beijing now, which is quite a long way from here.   乔先生现在住在北京，那里距离这儿很远。   I congratulate my neighbour, whose son has just won the election.   我祝贺我的邻居，他的儿子刚刚赢得选举。 非限制性定语从句的五个“不能” (1) 关系词不能用 that  (2) 关系词不能用 why，只能用 for which (3) 有且只有 as 能放整个句首，which 不能 (4) “介词+关系代词 其中的关系代词不能用 as。 介词 + which/ whom (5) 指人的关系代词作宾语时，只能用宾格 whom; 不能用 who 替换，也不能省略。 1. They have started an investigation, _____ are being kept secret. A. whose detail B. whose the details    C. the details of which D. the detail of it 2. Have you ever asked him the reason _____ may explain his absence? A. why B. for which C. which D. what 3. Mr Seal has changed a lot, and many of his friends say that he is not the same man _____. A. like he was B. as he used to be C. as he was used to D. like what he was 4. There were two rooms in the beach house, _____ served as a kitchen. A. the smaller of them B. the smallest of which C. the smaller of which D. smallest of which 5. Mont Blanc _____ we visited last summer, is the highest mountain in Europe. A. where    B. that    C. which    D. , which 6. He imagined various ways _____ he could teach her how to learn English well. A. / B. that        C. in which        D. A , B & C 7. The speed _____ light travels is said to be the maximum in the universe. A. in which B. by which C. at which D. from which 8. Can you think out a situation _____ this idiom can be used?  A. in which    B. that    C. where D. A & C 9. China has hundreds of islands, _____ is Taiwan. A. in which the largest B. its largest of which C. of which the largest D. which the largest 10. We ate in a luxurious restaurant but it wasn’t such a good dinner _____ she had promised us. A. that B. which C. as D. what