2017年春苏教版初三年级英语下册知识点总结.doc

2017年春苏教版初三年级英语下册知识点一动词不定式作主语To give is better than to receive.To reach there on foot is impossible.动词不定式作主语时，可以用it 代替，把实际主语不定式放在后面。Its better to give than to receive.Its impossible to reach there on foot.Its + adj + for sb. to do sth.Its not difficult for me to study English well.Its easy for him to work out this math problem.在这个句型中，如果形容词与不定式的逻辑主语关系密切，并且形容词用来说明逻辑主语的性质、品质、特点等，由of引出逻辑主语。这类形容词主要有nice, kind, good, wrong, right等。八. 动词不定式和疑问词连用动词不定式可以和疑问词what, which, how, where, when连用，构成不定式短语，可以作主语、宾语、表语、宾语补足语等。How to do is still a question.Have you decided when to leave?九. 动词不定式的否定形式动词不定式的否定式是在to前加not;不带to的不定式则在动词前加not. 如：Zhang Ming asked me not to stay at home all day. 张明要我不要整天呆在家里。My mother let me not do it by myself. 妈妈让我不要独自做这件事。被动语态英语有两种语态：主动语态和被动语态主动语态(The Active Voice)表示主语是动作的执行者。被动语态(The Passive Voice)表示主语是动作的承受者。构成：承受者+助动词be+及物动词的过去分词+by+执行者一般现在时：承受者+助动词am / is/are +及物动词的过去分词+by+执行者一般过去时：承受者+助动词was / were +及物动词的过去分词+by+执行者承受者+助动词shall / will be+及物动词的过去分词+by+执行者承受者+助动词 have/ has been+及物动词的过去分词+by+执行者承受者+ can /may/must/should +be+及物动词的过去分词+by+执行者被动语态用法：1)当我们不知道动作的执行者是谁，或者没有必要指出动作的执行者时，需用被动语态。2)当我们需要强调动作的承受者时,常用被动语态。3)如果需要说出动作的执行者, 用by引导出动作的执行者。主动语态变为被动语态时，其谓语动词的时态要与原句时态保持一致，其谓语动词的数要与新主语保持一致。主动语态变为被动语态时有以下几种情况：1)主语+谓语动词+宾语将主动语态的宾语变为被动语态的主语。(主动)We bought a book yesterday.(被动)The book was bought yesterday.2)主语+谓语动词+间接宾语+直接宾语将主动语态中一个宾语变为被动语态的主语。多数情况下将间接宾语变为主语。如果直接宾语变为主语时，间接宾语前要加介词to / for。(主动)He showed me a book yesterday.(被动)I was showed a book yesterday.(被动)The book was showed to me yesterday.3)主语+谓语动词+复合宾语含有一个由宾语加宾语补足语构成的复合宾语，变为被动语态时，将主动语态的宾语变为被动语态的主语，宾语补足语保留不变，成为主语补足语。(主动)I found him a good pupil. (宾语补足语)(被动)He was found a good pupil. (主语补足语)4)短语动词变为被动语态有些短语动词相当于一个及物动词，其后可以接宾语，因此它们也有被动语态，但短语动词是不可分割的整体，变为被动语态时不可去掉其后面的介词或副词。(主动)We should look after the patients very well.(被动)The patients should be looked after very well by us.5)宾语从句变为被动语态若主动语态中是宾语从句，变为被动语态时常用it作形式主语，而把真正的主语放在后面。Its said that he passed the exam.被动语态应注意的几个特殊问题：(1)不及物动词带介词和介词宾语，在变为被动语态时，仍然要带上介词。(主动)The students in class listen to the teacher carefully.(被动)The teacher is listened to carefully by the students in class.(2)当动词带有复合宾语时，并且宾补是省去“to”的动词不定式时，在被动语态中应加上“to”。(主动)They make do all the work.(被动)We were made to do all the work.(主动)We often hear her sing En