1、虛擬語氣類別用法例句if引導的條件從句與現(xiàn)在事實相反從句動詞：過去式（be用were）；主句動詞：should/would/could/might +動詞原形If he were here, he would help us.與過去事實相反從句動詞：had +過去分詞；主句動詞：should/would/could/might +have +過去分詞If I had been free, I would have visited you.與將來事實相反從句動詞：過去式/should +動詞原形/were +不定式；主句動詞:should/would/could/might +動詞原形If it

2、 should rain tomorrow, we would not go camping.其他狀語從句as if 引導的狀語從句中動詞用過去式或過去完成式They are talking as if they had been friends for years.even if/though 引導的從句, 與現(xiàn)在將來/事實相反:從句動詞用過去式,主句動詞用should/would +動詞原形。與過去事實相反:從句動詞：had +過去分詞；主句動詞：should/would +have +過去分詞Even if they were to fail, they wouldnt lose cou

3、rage.賓語從句demand, suggest, order, insist等表命令、建議、要求后的從句中動詞（should）+動詞原形He suggested that we not change our mind.wish后的從句中分別用過去式、過去完成式和could/would+動詞原形表示與現(xiàn)在、過去和將來情況相反I wish I could be a pop singer.主語從句在It is necessary/important/strange that, It is suggested/demanded/ordered/requested that等從句中，謂語動詞用（sho

4、uld）+動詞原形It is strange that such a person should be our friends.表語從句和同位語從句作idea, advice, order, demand, request等表命令、建議、要求的詞的表語從句和同位語從句，其謂語動詞用（should）+動詞原形My advice is that you (should) finish your homework first.The idea that you (should) go is right.其他句型中It is time that句型中動詞用過去式或should+動詞原形Its high

5、 time that we left.would rather所接的從句中動詞用過去式或者過去完成式I would rather you stayed at home now.If only句型中動詞常用過去式或者過去完成式，表示強烈的愿望If only our dream had come true!二 其他要注意的事項1. 虛擬語氣中出現(xiàn)be的過去式，只能用were。2. suggest表 “暗示、表明”和 insist表示 “堅持認為”,其后的賓語從句用陳述句語氣。 例如：You pale face suggests that you are ill. / He insisted tha

6、t he was right.3. if虛擬語氣條件句中如有had, should, were，可省略if, 將其提前引起倒裝。 例如：Were I you, I would remain. / Had you told me earlier, I wouldnt have missed it.4. 可用with, but for代替虛擬語氣條件句。例如：But for your help. I would have failed the exam. Without air there would be no life.as if/though, even if/though也可以不用虛擬，表

7、示真實的情況。例如：It looks as if it is going to rain.II、實戰(zhàn)演練用所給動詞的適當形式填空-If he _ (warn), he _ (not take) that food.-Luckily he was sent to the hospital immediately.When a pencil is partly in a glass of water, it looks as if it _ (break).I would rather they _ (not hear) of the news.I wish I _ (have) a room o

8、f my own when I was a child.To the surprise of the public, the identification of the cause of such a simple event _ (take) more than a year.Without air to hold some of the suns heat, the earth at night _ (be) freezing cold, too cold for us to stay.If I had worked harder at school, I _(sit) in a comf

9、ortable office now.Her pale face suggested that she _ (be) ill, and her colleagues suggested that she _ (have) a medical examination.I insisted he _ (go) to see a doctor, but he insisted nothing _ (be) wrong with him.He asks that he _ (give) an opportunity to explain why hes refused to go there.It is high time we _ (get) down to discussing this plan.If it were not for the fact that you _ (be) too busy, I would ask you to help me do this right now.Who do you suggest _