1．在“n. ／pron. ／num...＋prep. ＋ which”，“prep. ＋which”定语从句里。
1）They talked about a movie, the name of which I've never forgotten.
2）In Sydney the Chinese team got 28 gold medals, 16.5 of which were won by women.
3）China has thousands of islands, the largest of which is Taiwan.
4）Chaplin went to the states in 1910, by which time he had learnt to dance and act in comedies.
The dam, which is the biggest in the world, is 3,830 metres long.大坝长3,830米，是世界上最大的坝。
The moon, which doesn't give out light itself, is only a satellite of the earth.
Football, which is a very interesting game, is played all over the world.
1）Three of the biggest man-made projects in the world are the Great Wall of China, the Pyramids of Egypt and the Aswan High Dam, which is also in Egypt.
2）The Nile, which used to flood every year, now runs more regularly below the dam.
Mike's brother is a policeman, which he isn't.
Li Ling is very clever, which Li Long isn't.
My family, which has 35 people, is a large one.
Last year he went to Egypt, which is in Africa.