一、在英文中,，名詞或名詞短語主要充當(dāng)四種成分,，主語、賓語,、表語和同位語,。

    如果我們把句子當(dāng)作名詞來使用，分別在另一個句子中作主語,、賓語,、表語和同位語(見下表第二列)，于是就構(gòu)成了四種從句：主語從句、賓語從句,、表語從句和同位語從句,。因?yàn)橐詾檫@四種從句在本質(zhì)上相當(dāng)于名詞的作用，所以我們把他們統(tǒng)稱為名詞從句,。請看例句：

    二,、三種句子來充當(dāng)四種成分。(3,，4)

    上面說到名詞從句就是用一個完整句子充當(dāng)另一個句子的某種句子成分便構(gòu)成了具體某一名詞從句,。那么可以用什么樣的句子來充當(dāng)四種成分呢？答案是：

    三,、陳述句可分別充當(dāng)四種句子成分(名詞從句的重點(diǎn)內(nèi)容),，要在陳述句首加上他that。

    對于陳述句,，我們要在句首加上that,然后把“that+陳述句”分別放在另一個句子的四種位置即構(gòu)成四種名詞從句,。

    1。主語從句,?！皌hat+陳述句”在主語位置即成主語從句：

    Stuart is ugly。

    That Stuart is ugly is a fact.,。

    That Malaysians don’t speak good English is obvious,。

    更常見的是用it式主語置于句首，而將主語從句放在句末,。例如：

    It is a fact that Stuart is ugly,。

    It is obvious that Malaysians don’t speak good English。

    因此下面都是常見的主語從句句型：(￥)

    ①It is +過去分詞 +that 從句(found, believed, reported, thought, noted…)

    ②It is +形容詞 +that 從句(clear, possible, likely, natural, certain, fortunate, necessary, strange…)

    ③It is +名詞(短語) +that 從句(a pity, a shame, an honor, a good idea, a miracle…)

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    2. 賓語從句,?！皌hat+陳述句”在賓語位置即成賓語從句：

    I think (that) you turned off the light。

    We know (that) women love shopping,。

    She believed (that) her child was premature,。

    只有賓語從句中的that才可以省去，其他名從that不省,。

    3,。表語從句?！皌hat+陳述句”在表語位置即成表語從句：

    My idea is that the students should be more open to each other,。

    The reason is that he was careless and irresponsible。(考點(diǎn))

    4,。同位語從句,。“that+陳述句”在同位語位置即成同位語從句：

    所謂同位語,，就是用來補(bǔ)充說明名詞的成分,。

    The rumor that Tom washed his socks once a month turned out to be untrue。

    Our fathers brought forth upon this continent a new nation, conceived in liberty and dedicated to the proposition that all men are created equal,。

    A saying goes that tomorrow is another day,。

    四、一般疑問句可分別充當(dāng)四種句子成分,。1,、一般疑問句語序變成陳述語序。2,、用來whether或if引導(dǎo)。

    1,。主語從句： does she love dog-walking?

    Whether she loves dog-walking or not is unknown,。

    2,。賓語從句：

    I don’t know if/whether whether she loves dog-walking

    3,。表語從句：

    My concern is whether you are a student or not。

    4,。同位語從句：

    They are faced with the problems whether they should continue to play,。

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    補(bǔ)充：if whether區(qū)別

    1)if一般用于引導(dǎo)賓語從句，而whether可引導(dǎo)所有名詞從句

    If he comes or not makes no difference,。

    The question is if he will arrive,。

    2)if 不和or not直接連用,，一般不說 if or not,。但可以說 if … or not ,。而whether沒有此限制。

    I don’t know if or not he arrives,。

    I don’t know whether or not he arrives。

    五,、特殊疑問句可分別充當(dāng)四種句子成分,。特殊疑問句變成陳述句語序。

    There arose the question where we could get the loan。

    I have no idea what gender he is,。

    Why he refused to cooperate with us is still a mystery,。

    I don’t know how many letters I have written to her。

    NBA is what I am crazy about,。

    How China should develop next is a serious problem。

    Excuse me, can you tell me where the post office is?

    My question is where we are going to have our holidays,。

    The point is whose book is the most horrible,。

    Whoever comes will be welcomed。

    Whatever is left over is yours

    Do whatever you please。

    Read whichever books you please,。

    I'll give it to whichever of you wants it。

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    P.S. 最后說明：同位語從句多用that引導(dǎo)，少用whether, if以及代詞或副詞引導(dǎo),，因?yàn)槲覀兌嗍怯藐愂鼍溲a(bǔ)充名詞的內(nèi)容，而少用一般疑問句或特殊疑問句來補(bǔ)充名詞的內(nèi)容,。

    溫故知新：名詞從句就是用三種句子來分別充當(dāng)另外一個句子的四種句子成分。

    三種句子：

    四種成分：

    這三種句子不是直接放在另個句子中作成分,，而是要做以下調(diào)整：

    1)用陳述句作成分時,，要在句首加

    2)用一般問句作成分時,，先將疑問句換成語序，然后在句首加

    3)用特殊問句作成分時,，只需將疑問句換成

    語序,。

    下面是95年1月份的閱讀真題,，來感受下幾個難句吧,，若搞定名詞從句，那它們也就是小兒科,。

    It is a curious paradox that we think of the physical sciences as “hard”， the social sciences as “soft,，” and the biological sciences as somewhere in between. This is interpreted to mean that our knowledge of physical system is more certain than our knowledge of biological systems,， and these in turn are more certain than our knowledge of social systems. In terms of our capacity of sample the relevant universes， however,， and the probability that our images of these universes are at least approximately correct,， one suspects that a reverse order is more reasonable,。