It作形式主語常見用法

1、It 作形式主語常見句型1.lt + be + 形容詞+ that-從句可用于此句型的形容詞有 :wonderful, true ，good，right，wrong，( un)important，useless， surprising，disturbing,frightening,alarming,clear，unusual，lucky，certain, n ecessary 等。如： It is quite certain that he will be at the meeting.他將出席會議是無疑的。 It is surpris ing that he came late to sch

2、ool this morni ng.他今天早上遲至 U真 令人驚訝。 It is important that we (should) study hard.我們努力學習是很重要的。注意 :該句型中的形容詞是(un) important, necessary等時，從句應為(should )+ 動詞原形。It is important that we (should) learn English well.It is necessary that he (should) rember these words.2.It + be + 名詞 + that-從句適用該句型的名詞(詞組)有 :a pit

3、y， an honor， a good thing， a fact， a surprise， a question,a shame,a custom, a truth,our hope, no wonder, good/bad manners 等。如： It is a pity (that) you missed the sports meeti ng last week.你錯過了上周的運 動會太可惜了。 It is a fact that En glish is being accepted as an intern atio nal la nguage事實上 英語已經被作為一種國際語言而接

4、受了。3. Itseemappearhappen 的適當形式 that 從句。 It appeared that he was calm, but inside his heart was beating wildly with fear.4. It + be +過去分詞 +主語從句，這類過去分詞有：announ ced, believed, expected, hoped,decided, reported, said, shown等, 如：It is reported that 16 people were killed in the earthquake.It is not decide

5、d who will give the operation to the patient.5. It is time ( about time ,high time ) that .該句型中 that 后的從句應該用虛擬語氣，值得注意的是 常用過去時態(tài)表 示虛擬 有時也用 should +動詞原形， should 不能省。常譯為是(正 是)的時侯。It is time that children should go to bed.= It is time that children went to bed.6. It is the first ( second . ) time that .用

6、完成時態(tài)。至于用什么完成時態(tài)，由主句的謂語動詞的時態(tài)決定。如果 是一般現(xiàn)在時，后面從句用現(xiàn)在完成時態(tài)；如果是一般過去時，后面從句則用 過去完成時態(tài)。該結構中 that 可以省去； it 有時用 this 替換常譯為是第一(二)次。It is the first time I have been here.= This is the first time I have been here.7. It + be + adj./ n. (for sb. / of sb.) + to do sth該句型中的形容詞通常是表示事 物的特點或特征的如 difficult， hard， easy， impossible， necessary， important 等，此時用 fo r ；或表示人的性格特征或特點的如 nice， good， bad， kind，silly，foolish，wise，clever，careless，rude，brave，cruel，careful，grateful等，這時要用of。如： It is foolish of you to giv