1、从属连词,高二（4） 铁血绵羊,定义：从属连词这种连词是用以引导名词性从句和状语从句的.,从属连词在名词性从句中:that; weather; if,while, when, as 时间状语从句,while引导的状语从句中动词必须是持续性。,Please keep quiet while others are studying；,while 可用when代替，等于 “at the time that”, “during the time that”。,Please keep quiet when others are studying；,while, when, as 时间状语从句,When
2、I went into the lab, the teacher was doing an experiment.,He often makes mistakes when he is speaking English.,when引出的时间状语从句中的谓语动词可以是终止性的，也可以延续性的。因此主句和从句的谓语可以是一般时，进行时，或完成时。,while, when, as 时间状语从句,As (when, while) I was walking down the street, I noticed a police car in front of number 37.,as常可与when，
3、while通用，但强调“一边、一边”。,before 时间状语从句,Before I could get in a word he had measured me.,我还没来得及插话，他已经给我量好了尺寸。,He almost knocked me down before he saw me.,他几乎把我撞倒才看见我,till, until 时间状语从句,用于肯定句时，只与延续性动词连用，表示“到为止”。,They played volleyball until (till) it got dark.,He didnt go to bed until (till) the his father
4、 came back.,Not.until（till）谓语动词为非延续性动词，意为“某动作直到某时间才开始”,because, since, as 原因状语从句,He had to stay at home yesterday because he was ill.,如果原因构成句子的最主要部分,一般用because ,因此because引导的从句往往放在句末。用why提问的句子，一定用because回答。,because, since, as 原因状语从句,As you are tired, you had better rest. Since everyone is here, now l
5、ets begin.,原因已为人们所知，或不如句子的其他部分重要，就用as，或 since。since比as更正式。 as和since引导的从句一般放在句子的开头。,Although，though 让步状语从句,although, though引导的从句后，主句不能用but，但可用副词yet, still。,Although/ Though it rained all the morning, they still went on working.,once 条件状语从句,I dont believe he was once a thief. Once Aristotle had made u
6、p his mind that heavy objects always fell faster than light objects, he taught it as a truth to his students.,once作副词译“曾经”，作为连词译“一旦”,As if；as though 方式状语从句,He talks as if he knew all about it. It looks as if it is going to rain.,as if引导的方式状语从句及表语从句中，根据情况要使用虚拟语气。 如果很可能实现，可以用陈述语气。,whether, if 名词性从句,引导
7、主语从句、表语从句或同位语从句时，用whether，不用if。,whether可接不定式，而if则不可。,I havent decided whether to leave or not.,whether可作介词的宾语或置于句首表示强调，而if则不可。,whether和if均可引导宾语从句。 宾语从句为否定时只可用if。,I wonder if it doesnt rain.,I dont know whether/ if they will come or not. I dont know whether or not they will come. 引导宾语从句的whether和if常可与
8、or not连用。一般与 whether、if分开使用，它可与whether合起来使用。但不能与if合起来使用。,whether, if 名词性从句,if可用来引导条件状语从句，译“如果”，whether则不行。 If you work hard, you are sure to succeed.,whether, if 名词性从句,as,引导时间状语从句，意为“当时”；“一边.一边”。 As (he was) a young man, he was a storekeeper and later a postmaster. He sang as he worked. 引导方式状语从句，意为“象一样”。 We must do as the Party teaches us.,引导原因状语从句。意为“由于”， As you are tired, you had better rest. as引导让步状语从句。意为“虽然”、“尽管” Child as he is, he can do it well. as做为关系代词还可以引导定语从句 I have the same book as you.,as,thanks for watching!,
