It is 句型 1. It is + 被强调部分 + that ... 该句型是强调句型。将被强调的部分放在前面，其它部分置于that 之后。被强调部分可以是主语，宾语，表语或状语。强调的主语如果是人，that 可以由who 换用。如果把这种句型结构划掉后，应该是一个完整无缺的句子。这也是判断强调句型与其它从句的方法。 It was about 600 years ago that the first clock with a face and an hour hand was made. It was they that (who ) cleaned the classroom yesterday. It was in the street that I met her father. 2. It is not until + 被强调部分 + that ... 该句型也是强调句型。主要用于强凋时间状语，译成汉语＂直到．．．才．．．＂，可以说是 not ... until ... 的强调形式。 It was not until she took off her dark glasses that I realized she was a famous film star. = Not until she took off her dark glasses did I realize she was a famous film star. = I didn’t realize she was a famous film star until she took off her dark glasses. 3. 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．．．）＂ 是主语从句最常见的一种结构。 It is very clear that he’s round and tall like a tree. = That he’s round and tall like a tree is very clear. 4. 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。 It is important that we (should) learn English well. It is necessary that he (should) remember these words. 5. It is said (reported, learned....) 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. It is reported that another earth satellite has been put into orbit. ...
