羅玉南
名詞性從句是中學(xué)英語語法的重點和難點，現(xiàn)把在使用名詞性從句過程中應(yīng)注意的幾個方面總結(jié)以下，供同學(xué)們學(xué)習(xí)參考。
一忌 that與what混淆
what引導(dǎo)的名詞性從句意為“……的東西（事情）”或“什么”，相當于all that。如：
【誤】That he needs to get rid of smoking is your help．
【正】What he needs to get rid of smoking is your help．
【正】All (that) he needs to get rid of smoking is your help.that引導(dǎo)定語從句。
二忌 多that
引導(dǎo)名詞性從句的連接代詞who, whose, which, what, 連接副詞how, why, where, when和連詞if，whether等前，不可再用that。如：
【誤】I wonder that when they got to know each other．
【正】I wonder when they got to know each other．
三忌 少that
引導(dǎo)名詞性從句的that在句中無具體意思，但在下列情況下，that不可省略：
1．賓語從句被分隔或提前時；
2．賓語從句不止一個時；
3．引導(dǎo)主語從句、表語從句或同位語從句時。如：
【誤】We don’t doubt, in any case, he keeps his word．
【正】 We don’t doubt, in any case, that he keeps his word．
（插入語in any case將賓語從句與謂語動詞分隔開，故不可省略that。）
【誤】Everyone could see what was happening and poor Mary was nearly frightened．
【正】Everyone could see what was happening and that poor Mary was nearly frightened． （what was happening和that poor Mary was nearly frightened為并列的賓語從句，故不可將that 省略。）
【誤】The earth goes around the sun was not widely accepted at that time．
【正】That the earth goes around the sun was not widely accepted at that time． （that 引導(dǎo)主語從句時不可省略。）
【誤】The problem is fuels like coal and oil cause a lot of pollution．
【正】The problem is that fuels like coal and oil cause a lot of pollution．（that 引導(dǎo)表語從句時不可省略。）
【誤】We heard the news our team had won．
【正】We heard the news that our team had won．
that引導(dǎo)同位語從句時不可省略。
四忌 that, why和because三者混淆
有些名詞如reason，cause等作句子的主語時，其后的表語從句常用that引導(dǎo)，不可誤用because；because引導(dǎo)表語從句時常用于That’s because…這一句型，說明產(chǎn)生上述結(jié)果的原因；why引導(dǎo)名詞性從句說明由上述原因而導(dǎo)致的必然結(jié)果。如：
【誤】The reason why he hasn’t come is because he has not received the invitation．
【正】The reason why he hasn’t come is that he has not received the invitation．
【誤】I was very late for school this morning． That’s why I stayed up too late last night．
【正】I was very late for school this morning． That’s because I stayed up too late last night．（前面為結(jié)果，后面為原因。）
【正】I stayed up too late last night． That’s why I was very late for school this morning．（前面為原因，后面為結(jié)果。）
五忌 if, whether 和that三者混淆
if多在口語中引導(dǎo)賓語從句；在正式語體中或當引導(dǎo)主語從句、表語從句、同位語從句時則用whether；在doubt等后的賓語從句中熆隙ň涑８鷚hether或if引導(dǎo)的從句，否定句或疑問句則常跟that引導(dǎo)的從句。如：
【誤】If they will hold a sports meeting is not decided．
【正】Whether they will hold a sports meeting is not decided．
【誤】I doubt that that was what he wanted．
【正】I doubt if that was what he wanted．
六忌 語序倒裝
名詞性從句一律用陳述語序。如：
【誤】When will the meeting start is unknown to all．
【正】When the meeting will start is unknown to all．
七忌 從句時態(tài)錯誤
主句謂語動詞的時態(tài)為過去時態(tài)，名詞性從句謂語動詞的時態(tài)一般要受其影響，要用相應(yīng)的過去時態(tài)（表示客觀真理時用一般現(xiàn)在時）。如：
【誤】The man asked his wife where they’ll spend the night．
【正】The man asked his wife where they would spend the night．
【誤】We don’t know when he returns in the future．（誤為時間或條件狀語從句）
【正】We don’t know when he will return in the future。
八忌 從句語氣錯誤
名詞性從句經(jīng)常出現(xiàn)在用來表示一個并非基于事實的假設(shè)的虛擬語氣中。
一、.虛擬語氣中的主語從句。常見的句型有：
1．It is／was＋形容詞＋that＋主語（從句）＋（should）＋動詞原形……
常用在該句型中的形容詞有： important，impossible，normal，natural，necessary， sorry，strange，等，如：
【誤】It was necessary that the plan was planned carefully．
【正】It was necessary that the plan（should） be planned carefully．
2.表示“請求、命令、建議、決心”等意義的名詞。如：advice，demand，decision，，order，proposal，requirement， request，suggestion 等，如：
【誤】It is my suggestion that we will get everything ready tonight．
【正】It is my suggestion that we（should） get everything ready tonight．
3．It is ／was ＋動詞過去分詞＋ that＋主語（從句）＋（should）＋動詞原形……
用在該句型中的動詞過去分詞表示“請求、命令、建議”等意義。如：advised， begged，desired， demanded，insisted， ordered，proposed，requested， required，suggested 等，如：
【誤】It was suggested that each student must sing a song．
【正】It was suggested that each student（should）sing a song．
二、虛擬語氣中的表語從句與同位語從句。某些表示“建議、請求、命令”等意義的名詞后的表語從句或同位語從句需用“（should）＋動詞原形”構(gòu)成謂語。這類名詞有：advice，desire，decision， idea，order，plan，proposal， request，suggestion等，如：
【誤】We agree to his idea that we will put on a short play at the party．
【正】We agree to his idea that we（should）put on a short play at the party．
【誤】His suggestion was that we would go there by train．
【正】His suggestion was that we（should）go there by train．
另外，as if／as though 引導(dǎo)的表語從句，謂語動詞用：過去時表示與現(xiàn)在事實相反；過去完成時表示與過去事實相反。如： You look as if／though you were ill．
三、虛擬語氣中的賓語從句。
1.某些表示“愿望、請求、建議、命令、決心”等意義的動詞后的賓語從句需用“（should）＋動詞原形”構(gòu)成謂語。這類動詞有：advise，ask，demand，insist，order，propose，request，require，recommend，suggest， urge等，如：
【誤】The teacher suggested that we had a meeting．
【正】The teacher suggested that we（should）have a meeting．
2.動詞 wish 后的賓語從句，若表示不能實現(xiàn)的愿望，謂語動詞用過去時表示與現(xiàn)在事實相反的愿望；用過去完成時表示與過去事實相反的愿望；用“would ／could ／might＋動詞原形”表示與將來可能發(fā)生的事情相反的愿望。如：
【誤】How I wish I saw you yesterday!
【正】How I wish I had seen you yesterday!