that 與what 的混用：
1.That they are going to discuss at the meeting is how to increase food supply in the world.(錯誤)
What they are going to discuss at the meeting is how to increase food supply in the world.(正確)
注：that在引導(dǎo)名詞性從句時本身沒有意義，也不在從句中充當(dāng)任何成分；而what則表示“什么”“……的東西或事情”，在從句中充當(dāng)主語，賓語或表語等。上句中的what 應(yīng)充當(dāng)discuss的賓語。
if 與whether的混用：
2.If we will visit the Great Wall tomorrow has not been decided yet.(錯誤)
Whether we will visit the Great Wall tomorrow has not been decided yet.(正確）
注：if 與whether 引導(dǎo)賓語從句時往往可換，但在下面情況時常使用whether：作介詞的賓語時，見例①；在從句中提出兩種選擇時，見例②；從句提前時，見例③；引導(dǎo)主語從句，表語從句及同位語從句時，見例④。
①I worry about whether I hurt his feelings.
②She wasn’t sure whether she should laugh or cry.
③Whether he will come or not I don’t quite know.
④What many people are worried about is whether we will be able to build a better future.
We have some doubt whether they can complete the task on time.
that 與because 的混用:
3.(1)The reason why he was late for school was because he got up late.(錯誤)
The reason why he was late for school was that he got up late.(正確)
⑵Why farmland here is being lost is because farmers have cut down too many trees in recent years.(錯誤)
Why farmland here is being lost is because farmers have cut down too many trees in recent years.(正確)
注:reason作主語時引導(dǎo)的表語從句或why引導(dǎo)的名詞性從句時常用that不用because.
忽略連詞that:
4.These old languages are now threatened and may disappear is a serious matter to the people in Britain.(錯誤)
That these old languages are now threatened and may disappear is a serious matter to the people in Britain.(正確)
注：that在引導(dǎo)賓語從句時常常可省，但在下面情況時不可省去：賓語從句不止一個時，見例①；賓語從句與主句之間有插入語時，見例②；賓語從句為一個主從復(fù)合句時，見例③；引導(dǎo)主語從句，表語從句或同位語從句時，見例④。
①They complain (that) they have to work from morning till night, that it is hard to earn money, that they are bullied (欺負) by the policemen, or that the corporation leaders are seated lazily and enjoy the fruits of others’work.
②The teacher said, pleasantly and firmly , that we must overcome the difficulties.
③We believe that if we work harder, I will pass the National College Entrance Examination.
④The trouble is that she has lost his address.（表語從句)
Word came that China launched its first manned spaceship on Oct.15,2003.（同位語從句）
no matter who\what\which\how\where…與whoever\whatever\whichever\however\wherever…
5.No matter who breaks the rules will be punished.（錯誤)
Whoever breaks the rules will be punished.（正確)
注：whoever,whatever,whichever,however,wherever等連詞可以引導(dǎo)名詞性從句也可引導(dǎo)讓步狀語從句，而no matter who\what\which\how\where…只能引導(dǎo)讓步狀語從句。例如，
No matter how great the difficulty is, we ought to keep on.
Or: However great the difficulty is, we ought to keep on .
相似句型的混淆:
6.As is known to all that science plays an important part in the development of industry and agriculture.（錯誤)
As is known to all, science plays an important part in the development of industry and agriculture.（正確)
It is known to all that science plays an important part in the development of industry and agriculture.（正確)
注：as作為關(guān)系代詞引導(dǎo)的非限制性定語從句位于主句之前時，從句與主句之間要用逗號隔開。It作為形式主語將that 引導(dǎo)的主語從句后置時，that常常不能省。
1.That they are going to discuss at the meeting is how to increase food supply in the world.(錯誤)
What they are going to discuss at the meeting is how to increase food supply in the world.(正確)
注：that在引導(dǎo)名詞性從句時本身沒有意義，也不在從句中充當(dāng)任何成分；而what則表示“什么”“……的東西或事情”，在從句中充當(dāng)主語，賓語或表語等。上句中的what 應(yīng)充當(dāng)discuss的賓語。
if 與whether的混用：
2.If we will visit the Great Wall tomorrow has not been decided yet.(錯誤)
Whether we will visit the Great Wall tomorrow has not been decided yet.(正確）
注：if 與whether 引導(dǎo)賓語從句時往往可換，但在下面情況時常使用whether：作介詞的賓語時，見例①；在從句中提出兩種選擇時，見例②；從句提前時，見例③；引導(dǎo)主語從句，表語從句及同位語從句時，見例④。
①I worry about whether I hurt his feelings.
②She wasn’t sure whether she should laugh or cry.
③Whether he will come or not I don’t quite know.
④What many people are worried about is whether we will be able to build a better future.
We have some doubt whether they can complete the task on time.
that 與because 的混用:
3.(1)The reason why he was late for school was because he got up late.(錯誤)
The reason why he was late for school was that he got up late.(正確)
⑵Why farmland here is being lost is because farmers have cut down too many trees in recent years.(錯誤)
Why farmland here is being lost is because farmers have cut down too many trees in recent years.(正確)
注:reason作主語時引導(dǎo)的表語從句或why引導(dǎo)的名詞性從句時常用that不用because.
忽略連詞that:
4.These old languages are now threatened and may disappear is a serious matter to the people in Britain.(錯誤)
That these old languages are now threatened and may disappear is a serious matter to the people in Britain.(正確)
注：that在引導(dǎo)賓語從句時常常可省，但在下面情況時不可省去：賓語從句不止一個時，見例①；賓語從句與主句之間有插入語時，見例②；賓語從句為一個主從復(fù)合句時，見例③；引導(dǎo)主語從句，表語從句或同位語從句時，見例④。
①They complain (that) they have to work from morning till night, that it is hard to earn money, that they are bullied (欺負) by the policemen, or that the corporation leaders are seated lazily and enjoy the fruits of others’work.
②The teacher said, pleasantly and firmly , that we must overcome the difficulties.
③We believe that if we work harder, I will pass the National College Entrance Examination.
④The trouble is that she has lost his address.（表語從句)
Word came that China launched its first manned spaceship on Oct.15,2003.（同位語從句）
no matter who\what\which\how\where…與whoever\whatever\whichever\however\wherever…
5.No matter who breaks the rules will be punished.（錯誤)
Whoever breaks the rules will be punished.（正確)
注：whoever,whatever,whichever,however,wherever等連詞可以引導(dǎo)名詞性從句也可引導(dǎo)讓步狀語從句，而no matter who\what\which\how\where…只能引導(dǎo)讓步狀語從句。例如，
No matter how great the difficulty is, we ought to keep on.
Or: However great the difficulty is, we ought to keep on .
相似句型的混淆:
6.As is known to all that science plays an important part in the development of industry and agriculture.（錯誤)
As is known to all, science plays an important part in the development of industry and agriculture.（正確)
It is known to all that science plays an important part in the development of industry and agriculture.（正確)
注：as作為關(guān)系代詞引導(dǎo)的非限制性定語從句位于主句之前時，從句與主句之間要用逗號隔開。It作為形式主語將that 引導(dǎo)的主語從句后置時，that常常不能省。