引导词it的用法.docVIP

引导词it的用法 1.作形式主语?? 为了避免头重脚轻，英语里面常常把it放在句子的开头，而把真正作为主语的动名词，不定式和句子放在句子的后面去。请看下面的例子： It’s wrong to tell a tie. It took me ten minutes to get to the station. It’s no use getting there so early. It’s dangerous playing with fire. It doesn’t matter whether he will come or not. It’s a pity I didn’t think of it earlier.It’s not yet known where he has gone. 2.作形式宾语, 当复合句中，不定式短语，动名词短语和名词性从句作宾语时，常常it用作形式宾语，而把真正的宾语放在宾语补足语之后。请看例句：He feel it his duty to help others. The new medicine made it possible to treat this terrible disease. We thought it no use doing that. Out teacher thinks it no good learning without practice. I think it important that we should take part in the discussion. He soon made it clear why she hadn’t invited me to the party. Wouldn’t it better if you made an appointment to see him at the office? （三）it用于强调句型, 结构：It+动词be+被强调部分+who(whom)/that+其他部分 这个结构的一般疑问句形式为：被强调部分+who(whom)/that+其他部分 若是对特殊疑问词进行强调，其结构为: 特殊疑问词+be +it+that+其他部分 Was it in London that this happened? When was it that he left Beijing for Shanghai? How was it that you came here? He asked me that where it is that we will have the meeting. Not----until----句型的强调结构为it is not until-----that-------,that 后面要用肯定形式 Eg. My father didn’t return until 11 o’clock last night. It was not until 11 o’clock last night that my father returned. I didn’t realize she was a famous film star until she took off her dark glasses. (四) it的重要句型 1. It is clear ( obvious， true， possible， certain....) that ..... 该句型中it 是形式主语，真正的主语是that 引导的主语从句，常译为＂清楚（显然，真的，肯定．．．） 2. It is important ( necessary， right， strange， natural...) that ... 该句型和上一个同属一个句型；由于主句中的形容词不同，that 后的从句中要用虚拟语气（should + 动词原形），should 可以省去，建议记住该句型中的形容词。 eg. It is important that we (should) learn English well. 　　It is necessary that he (should) remember these words. 3. It is said (reported,learned,thought,believed,hoped,suggested,supposed,known....) that ... 该句型中的it 仍是形式主语，真正主语是that 引导的主语从句；该结构常译为＂据说（据报道，据悉．．．）　　 It is said that he has come to Beijing