高考总复习高一英语Unit2.pdfVIP

高考总复习高一英语Unit2 Unit 2 In the lab Lesson 5 1.Have you been in this lab before?你们往常进过那个实验室吗? Have(Has) been to 意为“到过什么地点”。例如: I have been to the Great Wa many times.我去过长城多次。 A:Where have you been?你去哪里了? B:I ve been to the library.我去图书馆了。 Have you ever been abroad before?你往常出过国吗? 【注意】have(has) been to 和 have(has) gone to 的区别:have(has) gone to 表示:已去某地， 或已到达某地。例如: My husband has gone to London today.我夫君今天去伦敦了。 It s seven already. A the teachers have gone home.现在差不多七点了，所有的老师都回家 了。 2. make sure... make sure 表示“务必”，“确信”，“弄明白”，后面常接 of/about sth. 或that 引导的宾语 从句。例如: Make sure(that) you wi arrive there on time.你务必准时到这。 I know there s a train this afternoon，but I must make sure of the time.我明白今天下午有列 火车，但我必须弄清晰(发车)时刻。 注意:make sure 后通常不接不定式。 误:Make sure to shut the windows. 正:Make sure that you shut the windows. 正:Make sure that the windows are shut. 3. first of a first of a 意思为“第一，最重要的”，是first 的强调形式，常用于句首。例如: First of a ， I d like to say how glad I m here. I have a lot to say，but first of a ，I want to thank you for your warm welcome. 【注意】和at first 的区别: at first 意为“开始，起初”，相当于 at the beginning ，通常指某事刚发生时的情形，但 后来往往发生了变化。例如: At first he knew nobody here， but now he has made a lot of friends. 4.turn off turn off 意为“切断( 电源)，关掉( 自来水、电灯、收音机等) ”，其反义词为turn on 。注 意那个地点不能用close 或open 。 例如: Please turn off the lights before you go out. As soon as he got home，he turned on TV. 5.Once you are in here， listen to your teacher.一旦你们进到那个地点，就要听老师的。 once 那个地点用作连词，相当于 from the moment that，when，意思为“一旦，一…… 就”，引导时刻状语从句。例如: Once she arrives，we can start. Once he understands why he must study， he wi study hard. once 还可用作副词，有“一次”或“曾经”的意思。例如: They went there once a week. 6.Don t touch anything unless your teacher te s you to. 除非老师让你动，否则就不要动任