[語法講解]：“虛擬語氣”

　　考生應該注意以下幾種虛擬語氣的形式：

　　第一種：由 “ if ”引導的虛擬句子

　　(1). 與現(xiàn)在的事實相反：[If --- + were/did---, --- + would do---]

　　If I were you , I would marry him.

　　如果我是你,就會嫁給他。

　　(2). 與過去的事實相反：[If --- + had done---, --- +would have done---]

　　If you had worked hard , you would have passed the exam.

　　如果你用功學習,就會通過考試了。

　　(3). 與將來的事實可能相反：[If ---+ should do---, ---+ would do---]

　　If it should rain tomorrow , what would you do ?

　　如果明天下雨,你怎么辦?

　　第二種：用在表示要求、建議、命令等的名詞從句中

　　從句謂語形式為：“---(should ) + do sth”(在美語中should常省去) 。

　　類似用法的動詞有：

　　insist (堅持) , suggest (建議) , order(命令) , propose (建議) , demand (要求) , command (命令) , advise (建議) , desire (要求、請求) , request (請求) , require (需要、要求) , ask (要求) , prefer (寧愿), recommend(推薦) , arrange ( 安排) , advocate ( 擁護、提倡) ,maintain(堅決主張)等后面的賓語從句中。

　　第三種：用在“It + be + important (,necessary , natural , essential , strange , absurd , amazing , annoying , desirable, surprising , vital , advisable , anxious , compulsory , crucial , imperative , eager , fitting , possible , impossible , improper , obligatory , probable , preferable , strange , urgent 等, 以及insisted , suggested , ordered , requested , arranged , recommended 等) + that ---”結構中的that 引導的主語從句中

　　第四種：用在It is time that --- 結構中, 表示“該干某事了”, 含建議的意思, 用動詞過去式。

　　It is time (that) we went to bed .

　　咱們該睡覺了。

　　注意: time 前可加about (表示“大約”) 或high(表示“強調(diào)”) 等。

　　4.Some psychologists claim that people (出門在外時可能會感到孤獨).