定语从句中：只用that而不用which的五种情况引导定语从句的关系代词有：that（指人或物），which（指物），who (指人）。指人时可用that或who ；指物时可用that 或which ；但有时只能用that，不能用which。常见的情况有下列五种：1） 当先行词是：all , any , anything , everything , nothing the one, much, few, little或被它们修饰时。例如：Is there anything that I can do for you ? 有什么可以为你做的吗？All that can be done must be done .凡是能做的都必须做。2）当先行词被形容词的最高级或序数词修饰时。例如：That is one of the most interesting books that are sold in the bookshop .那是这家书店出售的最有趣的书之一。The first thing that we should do is to get some food .我们该做的第一件事是弄点吃的。3）当先行词有：the only , the very , the same , the last 等修饰时。例如：My necklace is not the only thing thats missing .我的项链不仅是丢掉的东西。4）当主句以who或which开头时，定语从句中引导词用that ,不用which 或 who 。以避免重复。例如：Who is the girl that is wearing a red coat ?正穿一件红色外套的女孩子是谁？5）当先行词既有人又有物时，用that 。例如：The writer and his novel that you have just talked about are really well known .你刚才谈起的那位作家以及他的小说确实很著名。