定语从句中只用that不用which的，和只用which不用that的情况？

1、 定语从句中宜用that而不用which的情况 1) 先行词为all much little everything anything nothing none few the one 等不定代词； e.g. I mean the one that was bought yesterday. 2) 先行词被形容词最高级或被only any few little no all one of等修饰时； e.g. It’s the most important task that should be finished soon. 3) 先行词为数词或被序数词（包括last）所修饰时； e.g. Look at these flowers. You can see the two that you gave me. 4) 先行词中既有人又有物时； e.g. We were deeply impressed by the teachers and schools that we had visited. 5) 主语中已有who和which的； 6) 先行词在主句中做表语或关系代词在从句中做表语时； e.g. It’s book that will help you a lot. My hometown is no long the place that it used to be. 2、 不宜用that的情况 1) 关系代词前有介词时； e.g. This is the room in which Lu Xun lived. 2) 非限定性定语从句中； e.g. He has a daughter, who works in a hospital. 3) 先行词本身是that时； e.g. The clock is that which tells the time 2) 只能用that作为定语从句的关系代词的情况 a) 在不定代词，如：anything, nothing, everything, all, much, few, any, little等作先行词时，只用that，不用which。 All that is needed is a supply of oil. Finally, the thief handed everything that he had stolen to the police. b) 先行词有the only, the very, the just修饰时，只用that。 He is the very man that helped the girl out of the water . c) 先行词为序数词(the last)、数词、形容词最高级时，只用that。. The first English book that I read was “The Prince and the Pauper” by Mark Twin . d) 先行词既有人，又有物时。 He talked about the teachers and schools that he visited . e)当主句是以who 或which 开始的特殊疑问句时，用that 以避免重复。 Who is the person that is standing at the gate . f)关系代词在从句中做表语 He is not the man that he used to be