Unit 1 Discover Useful Structures 课件-2022-2023学年高中英语人教版（2019）选择性必修第一册

选择性必修一 Unit 1 定语从句是对前面出现的名词、代词(统称先行词)或主句进行限定或解释说明。 限定本身指代不明确的先行词时，用限定性从句，从句前不用逗号；对本身已经指代 明确的表示一定范围内的独一无二的人或物(加only的除外)或专有名词进行解释说明时， 用逗号把从句与主句隔开，称非限定性从句。that和why不能用于非限定性从句。 定语从句的引导词判断是学习和使用定语从句的关键，其判断依据如下： 一、在从句中的作用：在从句中作主语、宾语、表语和定语时，引导词用关系代词； 在从句中作状语时，引导词用关系副词 二、看先行词所表示的意义：作主语、宾语、表语和定语时，指人时，分别用who / that, (whom / who / that), (that 特指 / which泛指), whose；指事 物时，分别用which / that, (that / which), (that 特指/ which 泛指), whose (物主) / which 作状语时，指时间用when / “介词+which”, 指地点用where / “介词+which”, 指原因用why(不用于非限定性从句)/for which 判定引导词时，还要考虑特殊情况： 1、从句是限定性的还是非限定性的：非限定性从句必须保留引导词，且不能用that和 why引导 2、是限定还是解释说明，是解释说明的是先行词还是主句(用as或which)，非限定性从 句是否表示“正如、像”的意思(是则用as，as是关系代词) 3、是否属于只能用that引导或只能用which引导的特殊用法 4、是否是“介词+关系代词”结构 5、其他特殊情况(如引导词的省略和特殊的先行词occasion等) 限定性从句中关系代词的省略情况： 1. She is not the girl (whom / that) I loved before. (关系代词在从句中作宾语) 2. He is still the boy (that) he used to be. (关系代词在从句中作表语) 3. Environmental pollution is an issue (that / which) most people are concerned about. (关系代词作介词宾语，但介词在从句末尾) 先行词是人用that的情况： 1. Who is the man that is singing on the stage? (疑问词who开头的句子) 2. She is not the girl that she used to be. (关系代词在从句中作表语) 3. This is the very person that we are looking for. (先行词被the very, the right, the only修饰) 先行词是人用who的情况： 1. Those who want to go to the cinema will have to wait at the gate of the school. (先行词是one, ones, anybody, all, none, those 等) 2. The girl that helped you yesterday is the league member who studies very hard. (句中有两个定语从句，一个用了that，另外一个用who) 3. There are many young people who are fond of playing video games. (there be 结构中) 4. Tom, who is my best friend, has gone abroad to study. (非限定性定语从句) 先行词是物用which的情况： 1. She failed th