難點形成原因：
    1.學(xué)習(xí)過程太零碎，不系統(tǒng)。
    2.分不清什么時候使用，怎么使用。
    3.一些固定用法記不住。
    解決辦法：
    虛擬語氣通過謂語動詞的特殊形式來表示。由于虛擬語氣表達(dá)的是與事實相反的行為狀態(tài)，其謂語動詞的變化不同于陳述語氣，這也是大家感到困惑和容易出錯的地方。做此類題目時，關(guān)鍵要迅速發(fā)現(xiàn)解題信息詞，確定虛擬語氣類型，然后按各類虛擬語氣的特定表達(dá)方式確定動詞的形式。
    用法講解：
    虛擬語氣表示說的話不是事實，或者是不可能發(fā)生的情況，而僅是一種愿望、建議或者與事實相反的假設(shè)等。一般常用于正式的書面語中。
    1.條件從句中的虛擬語氣
    虛擬情況
    條件從句謂語形式
    主句謂語形式
    典型例句
    與現(xiàn)在的事實相反
    did/were
    would do
    I would ask George to lend us the money if I knew him. ? ?
    與過去事實相反
    had done
    would have done
    If Bob had come with us, he would have had a good time. ? ?
    與將來事實相反
    did/were
    would do
    We would stay at home if it should rain tomorrow.
    If I were to do the examination I would do it some other way.
    were to do
    should do
    混合虛擬
    從句與過去事實相反
    主句與現(xiàn)在事實相反
    had done
    would do
    It is hard for me to imagine what I would be doing today if I had not fallen in love, at the age of seven, with the Melinda Cox Library in my hometown. (2002上海)
    含蓄虛擬條件句
    有時假設(shè)的情況并不以條件從句表示出來，而是通過一個介詞短語或其他方式表示。通常的詞或短語有：without"如果沒有", but for "要不是", but that, otherwise, or, but等。
    He hesitated for a moment before kicking the ball, otherwise he would have scored a goal. (2001上海春季)
    But for my classmates’ help, I would not have finished the work in time. (2004三級題)
    Without heat and sunlight, plants on the earth would not grow well. ( 2004三級題)
    注意：在虛擬條件句中，若有動詞were, should或had(+過去分詞)，可以省略if，且把這三個詞放在主句之前，變成倒裝句。如：
    What would have happened, had Bob walked farther, as far as the riverbank? (2001上海)
    Had I realized you were busy, I wouldn't have bothered you with my questions. (1996三級題)
    Had the weather been good, the children could have gone out for a walk. (2001三級題)
    Had he taken the advice of his friends, he would not have suffered such a heavy loss in his business. (2004三級題)
    2. 賓語從句中的虛擬語氣
    動詞
    虛擬情況
    賓語從句謂語形式
    典型例句
    wish
    與將來事實相反
    would do
    I wish I would go to the Mars one day.
    與現(xiàn)在的事實相反
    did/were
    How I wish every family had a large house with a beautiful garden. (2002上海春季)
    與過去事實相反
    had done
    Peter wishes that he had studied law instead of literature when he was in college. (2000三級題)
    would rather
    與將來或現(xiàn)在事實相反
    did /were
    – Do you mind if I keep pets in this building?
    -- I’d rather you didn’t, actually. (2000上海)
    命令order , command
    要求request, demand, insist
    建議suggest, propose, recommend, advise
    should do (should可以省略)
    Who do you suggest be sent to work there? (2002上海)
    had hoped“本來想要，本來希望”
    would done
    I had hoped that she would go to the U.S. and study there, but she said she liked to stay in China.
    注意：表命令、請求、建議的詞order; request, demand, insist; suggest, propose, recommend, advise其表語從句、同位語從句、主語從句的謂語動詞都要用should do的形式，should可以省略。但當(dāng)insist表示 “堅持說”, suggest表示 “暗示,表明”時,不用虛擬語氣。
    The general's command was that the soldiers leave their fort and carry out more important tasks. (表語從句, 省略should, 2002三級題)
    Her suggestion that everybody sing a song was not appreciated. (同位語從句, 省略should, 2001三級題)
    She insisted that he was wrong. 她堅持說他錯了。
    His pale face suggests that he is in bad health. 他面色蒼白，說明他身體不好。