2019屆中考英語虛擬語氣專題復習

虛擬語氣是通過特殊的謂語動詞形式來表達的愿望、假設、懷疑、猜測或建議等語氣，它不表示客觀存在。
1、虛擬語氣用于條件狀語從句中
（1）表示與現在事實相反的假設，條件狀語從句中的謂語動詞用“過去式（be動詞的過去式用were）”，而主句中的謂語動詞用“would / should/ could / might + 動詞原形”。如：
if i were a boy, i would join the army.
if the had time, she should go with you.
（2）表示與過去的事實相反，條件狀語從句中的謂語動詞用過去完成時，主句中的謂語動詞則用“would / should / might / could + have +過去分詞”。如：
if he had taken my advice, he would have succeeded in the competition.
（3）表示與將來事實相反，條件狀語從句中的謂語動詞一般過去時或should(were to) + 動詞原形，而主句中的謂語動詞則用would / should/could might + 動詞原形。如：
if it were to rain tomorrow, the football match would be put off.
（4）當條件狀語從句表示的行為和主句表示的行為所發生的時間不一致時，動詞的形式要根據它所表示的時間作相應調整。如：
if they had worked hard, they would be very tired.(從句說的是過去，主句指的是現在)
以下表格是虛擬語氣用于條件狀語從句中時，主句和從句謂語動詞的形式：
  條件狀語從句  主句  與過去事實相反  had + 過去分詞 should /would/could/might + have + 過去分詞  與現在事實相反  一般過去時(be用were) would/should/could/might + 動詞原形  與將來事實相反 
一般過去時或should(were to) + 動詞原形
would/should/cold/might + 動詞原形

有時侯在使用時可省略if，句子則可換成下列形式，即“were / had / should +主語”。如：
were i a boy, i would join the army.
had he taken my advice, he would have succeeded.
were it not for the expense, i would go to britain.
2、虛擬語氣用于名詞性從句
（1）虛擬語氣在賓語從句中的運用。
①“wish + 賓語從句”表示不能實現的愿望，譯為“要是……就好了”等。表示現在不能實現的愿望，從句中的謂語動詞用一般過去時；表示將來不能實現的愿望，從句中的謂語動詞用“would/could + 動詞原形”；表示過去不能實現的愿望，從句中的謂語動詞用“had + 過去分詞”或“could(should) + have + 過去分詞”。如：
i wish it were spring all the year round.
i wish i had known the answer.
i wish i could fly like a bird.
②在表示建議、要求、命令等的動詞suggest、advise、propose、demand、require、insist request、command、order等后的賓語從句中，謂語動詞用should + 動詞原形或是動詞原形。如：
she suggested we (should)leave here at once.
the doctor ordered she should be operated.
（2）虛擬語氣在同位語從句和表語從句中的運用。
作表示建議、要求、命令等的名詞advise、idea、order、demand、plan、proposal、suggestion、request等的表語從句和同位語從句，從句中的謂語動詞用“（should） + 動詞原形”。如：