定語從句（用不用that）
(1)只能用關系代詞that的幾種情況：
1. 先行詞為something, nothing, everything, anything等不定代詞時；或者先行詞為all, each, few, much, no, some, any等不定代詞(或被這些限定代詞修飾)時。如：There is little that I can do. / All the books that you need are here.
2. 先行詞是序數詞或形容詞最高級(或被序數詞或形容詞最高級修飾)時。如：This is the best book that I have read about American culture.
3. 先行詞為the way, the time, the place等時，關系代詞常用that代替when, where, in which，又可省略(非正式場合)。如：I don’t like the way (that) he spoke to his mother. / This is the first time (that) I have given you a lesson in French.
4. 先行詞既有人也有物時。如：He talked about the teachers and schools that he had visited.
5. 先行詞被the only, the very, the just等詞修飾時。如：This is the only school that he has visited.
6. 關系代詞在從句中作表語時。如：He is not the young man (that) he used to be.
7. 主句是Who/Which特殊疑問句時，為了避免重復與混淆，定語從句引導詞用that。
1. 在非限制性定語從句中。如：Henry Royce did not like his car, that often broke down.
2. 在關系詞前有介詞時。如：We depend on the land from which we get our food.
3. 先行詞是those, he, they, one, anyone, someone, everyone等詞時，關系詞常用who，而不用that。如：One who does not work hard will never succeed.
4. 關系詞離先行詞較遠時。如：Do you know the woman in blue with a baby on her back who is working in the fields?
5. 主句是there be句型時(指人)。如：There is a big man outside who wants to see you.
6. 先行詞部分包含有that時，為了避免重復與混淆，關系詞常用who/which，而不用that。
