状语从句时间原因.ppt

Unit 4,Grammar,Entertainment,(一)Adverbial clause of time:,when、while, 、as 、after、before、since 、until/till、every/each time、whenever,1、before = at an earlier time than,2、after =at a later time than,3、while and as = at the same time as while is usually used with longer actions and as with shorter actions,4、Since =from the time that,5、until = up to the time that when speaking ,we can use till instead of until,when 当时侯 就在这时She was doing her homework when she had a good idea.,when、while、as 的区别,while 当时侯（从句的谓语必须是持续性动词，与主句谓语同时进行且用进行时态；或从句用“be+表语”表示状态） 趁之时； 然而(并列句)； 尽管,as 当时，在的同时； 一边一边； 随着.As time went by, he realized his mistake.,1) _he comes here tomorrow, I will call you. (at the time that) 2) Henry is in charge of the office _ Mr.Smith is away. (during the time that) He learned to speak English _ he was here. 4) I like tea _ she likes coffee. 5) _they were picking tea, the girls were singing happily. 6) She sang _ she worked.,When,while,while,while,As,as,Exercises,before： 1、I had entered the classroom before I heard the bell. 2、Youd better write it down before you forget it. 3、Look before you leap.（三思而后行） 4、It will be half a year before I come here again. 5、It was less than one month before they got the result. 注意英汉的差别,1、“在之前；才； 2、还没来得及就； 3、没过多长时间就； 4、趁还没； 5、一就”等。,it + be + time + before 句型归纳 1. It was not long before she learned those poems by heart. 2. It was long before the police arrived. 3. It will be hours before he makes a decision. 4. It will not be hours before we meet again.,用不了多久又一条新的遂道就要建成穿过浦江。 It wont be long before a new tunnel is built across the HuangPu River. 过了好多年他才知道谁在他困难时帮助了他。 It was many years before he knew who had helped him when he was in trouble.,Since的用法 eg: It is five years since she came back to settle down from abroad. eg: It is three years since I began to smoke. eg: It is three years since I smoked a cigarette. eg: It is four years since he lived here.,注意：这个句型的时间要从since从句中作谓语的动作或状态结束后算起；如果since从句的谓语是持续性或反复性动词时，要按否定来理解。,It is / has been + 时间段 + since “自从以来已有多长时间了”,the moment, the minute, the second, the instant, （结合报纸） 1、The engine started the minute the button was pressed. 2、The lamp will light the moment you press the button. 3、I knew I had made a mistake the instant I had done it.,一就,as soon as,as soon as,no soonerthan, hardlywhen, scarcelywhen,注意: no soonerthan, hardlywhen, scarcelywhen中否定词放句首时 主句要部分倒装，并且用过去完成时态）,一就,1、 Hardly / Scarcely had I got home when it began to rain. 2、 No sooner had I got home than it began to rain,Until / till,用于肯定句，句子的谓语动词必须是延续性动词，如： It was largely forgotten until it was discovered again in 1858. I studied English until 9 oclock last night. Continue in this direction until you see a sign. 注意： until可以位于句首，till则不能; Until you told me ， I had no idea of it. I will wait for you till/until you come back.,2.not until - 直到才,I didnt go to sleep until 11 oclock. He didnt leave the office until he finished the work. The little boy didnt stop crying until he saw his mother. till/until引导的时间状语从句，如果主句中的动词为瞬间动词，主句必须用否定形式。,Not until 在句首，主句用倒装, 如： I didnt go to sleep until 11 oclock. Not until 11 oclock did I go to sleep. He didnt leave the office until he finished the work. Not until he finished the work did he leave the office. The little boy didnt stop crying until he saw his mother. Not until he saw his mother did the little boy stop crying. You will not understand the beauty until you see it with your own eyes. Not until you see it with your own eyes will you understand the beauty.,It is/was not untilthat为强调结构 He didnt leave the office until he finished the work. It was not until he finished the work that he left the office. I didnt go to sleep until 11 oclock. It was not until 11 oclock that I went to sleep. You will not understand the beauty until you see it with your own eyes. It is not until you see it with your own eyes that you will understand the beauty.,他直到病了才意识到健康的重要性。,1、He didnt realize the importance of health until he was ill.,2、Not until he was ill did he realize the importance of health.,3、It was not until he was ill that he realized the importance of health.,（二）Adverbial Clauses of Reason because, since, as, now that, for,1） because语势最强，用来说明人所不知的原因， 回答why提出的问题。当原因是显而易见的或已 为人们所知，就用as或 since。 1、I didnt go because I was afraid. 2、Since /As the weather is so bad, we have to delay our journey. 2） 由because引导的从句如果放在句末，且前面有 逗号，则可以用for来代替。但如果不是说明直接 原因，而是多种情况加以推断，就只能用for。 1、He is absent today, because / for he is ill. 2、He must be ill, for he is absent today.,because, since, as和for,其他类的状语从句和连接词,地点：where,