常用it 作形式主语的句型结构 ◇ It + be +形容词+ that-从句 可用于此句型的形容词有: wonderful, true，good，right，wrong，（un）important，useless，surprising，clear，unusual，lucky，certain, necessary等。 如： ① It is quite certain that he will be at the meeting. ② It is surprising that he came late to school this morning. ③ It is important that we (should) study hard 注意: 该句型中的形容词是（un）important, necessary等时，从句应为 (should )+动词原形。 ◇ It + be + -ed 分词+ that-从句 适用该句型的过去分词主要有: said, reported, announced, hoped, thought，told，believed，expected，decided，suggested, known 等。如： ① It is hoped that one day they will have enough animals to set them free ② It is well known that the earth goes around the sun. ③ It is suggested that the sports meeting (should ) be put off until next week. 注意: 该句型的过去分词是 suggested 时，从句应为 (should )+动词原形。 ◇ It + be +名词+ that-从句 适用该句型的名词（词组）有: a pity，an honor，a good thing，a fact，a surprise，good news, one’s duty 等。 如： ① It is a pity (that) you missed the sports meeting last week. ② It is a fact that English is being accepted as an international language. ◇ It ＋seem／ appear／ happen 的适当形式＋that 从句。该句型常可以转换成含不定式的简单句。如： ① It seems that there is a big waste pipe coming down from the town. → There seems to be a big waste pipe coming down from the town. ② He appeared to becalm, but inside his heart was beating wildly with fear. → It appeared that he was calm, but inside his heart was beating wildly with fear. ◇ It doesn't matter ( It’s no wonder; It doesn’t make much difference 等) ＋ when/ where/ which/ whether 等从句。 如： ① Does it matter if he can't finish the...
