Unit8语法精讲及精练 2023-2024学年牛津译林版英语八年级上册

译林8AUnit8语法精讲精练——when, while, as 【简捷记忆】 双长while双短as; 主短从长皆可用； 主长从短as, when; 随着as趁机while. （注意：长——指使用进行时态） 1、“主长从长”（双长）型：即主句和从句为两个同时进行的动作或存在的状态, 通常要用while。如： 　　 I always listen to the radio while I’m driving. 我总是一边开车一边听收音机。 　　 He didn’t ask me in; he kept me standing at the door while he was reading the message. 　　 　　2、“主短从长”型：即主句是一个短暂性的动作, 而从句是一个持续性动作, 此时三者都可用。如： Jim hurt his arm while/when/as he was playing tennis. 　 　　3、“主长从短”型：即主句是一个持续性动作, 而从句是一个短暂性动作, 此时可用as或when如： 　　 It was raining hard when/as we arrived. 我们到达时正下着大雨。 　　 When/As he came in, I was listening to the radio. 他进来时, 我在听收音机。 4、表示主句动作伴随从句动作同时发展变化, 有“随着”的意思, 习惯上用as。如： 　　 The room grew colder as the fire burnt down. 随着炉火逐渐减弱, 房间越来越冷。 　　 As time goes by my memory seems to get worse. 随着时间的流逝, 我的记忆力似乎越来越差。 　　 若从句所表示的“当……的时候”具有“趁机”的意味, 则通常用while。如： Strike while the iron is hot. 趁热打铁。 　　　　有时也用when。如：He stole the money when no one was by. 他趁旁边无人时把钱偷走了。 【注意】 ①两句主语相同时，when和while之后可接现在分词、介词短语、形容词等构成省略句。如： 　　 When/While reading, he fell asleep. 他看书时睡着了。 　　 When/While in trouble, ask her for help. 遇到麻烦的时候你就去找她帮忙。 　　 You must study hard while young, or you will regret when old. 你趁年轻时必须努力学习, 不然到老了你会后悔的。 ②when(=at this moment)表示并列关系，正在这个时候。 I was walking along the street when I happened to meet an old fiend of mine. I was walking alone through the desert when I met two Arabs. 【经典练习】 I. 用when、while或as填空 1. I was doing my lessons ______________ Mary came in. 2. The students sat quietly ______________ the teacher was telling them a story. 3. _____________ he talked on, he became more and more excited. 4. _________ he was speaking, everybody listened carefully. 5. _______ she grew older, she became more responsible. 6. He came just _____________ I reached the door. 7. I was about to go out _________ a visitor came. 8. He learned to speak German _________ he was in Berlin. 9. ___________ we were waiting for the bus, a girl ran up to us. 10. Even ____________ she was a child she had already thou