2019中考英语复习—it形式主语用法及练习

It作形式主语常见句型 动词不定式，动名词或主语从句作主语时，通常把它们放在谓语动词前，而用it作形式主语，放到句首，常见句型有： 1. It + be + 形容词+主语从句，如： It is uncertain whether he can come to Jenny’s birthday party or not. 2. It + be + 名词词组 + 主语从句，这类名词有：a fact, a pity, a shame, an honour，a question等，如： It’s a pity that you missed the exciting football match. It remains a question whether he will come or not. 3. It + be + 过去分词 + 主语从句，这类过去分词有：announced, believed, expected, hoped, decided, reported, said, shown等， 如： It is reported that 16 people were killed in the earthquake. It is not decided who will give the operation to the patient. 4. It + 不及物动词(seem, appear, happen等) + 主语从句, 这类不及物动词有：appear, happen, seem等， 如： It seemed that he didn’t tell the truth. It happened that I was out when he called. 5. It + be + 形容词 + for sb.）+ 动词不定式 这类句型常用形容词easy, difficult, hard, important, possible，wise等作表语，有时候为了强调不定式动作的执行者，常在不定式前加for sb，如： It’s necessary for the young to master two foreign language. It is unwise to give the children whatever they want. 这类形容词有：eas