這個(gè)要視情況而定的.引導(dǎo)詞分為四種,分別是：
由從屬連詞that引導(dǎo)的賓語(yǔ)從句
由從屬連詞 whether,if 引導(dǎo)的賓語(yǔ)從句
由連接代詞 Who,whom,whose,which,what引導(dǎo)的賓語(yǔ)從句
由連接副詞 where,how,why,when引導(dǎo)的賓語(yǔ)從句
由從屬連詞that引導(dǎo)的賓語(yǔ)從句
that 在句中無(wú)詞匯意義,在從句中不能充當(dāng)成分,在口語(yǔ)當(dāng)中往往省略
如：I hear (that) he will be back in an hour
由從屬連詞whether,if 引導(dǎo)的賓語(yǔ)從句
if/ whether “是否”,說(shuō)明對(duì)陳述的事物不明確或不清楚.常用在ask,wonder,can(could) you tell me 等后.
如：I want to know if (whether) he will go tothe park with us
只能用whether 不能用if
在介詞后面
如：I’m thinking of whether we should go fishing.
在動(dòng)詞不定式前：
They asked me whether to go skating
當(dāng)與or not連用,或提出兩種選擇時(shí)
Mary asked whether I was doing my homework ornot.
賓語(yǔ)從句提前時(shí)：
Whether this is true or not,I can’t say
由連接代詞 Who,whom,whose,which,what 和連接副詞 where,how,why,when引導(dǎo)的賓從(代詞或副詞連接主句和從句,并在從句中擔(dān)任句子成分,具有一定的意義,不可省略)
He asked who could answer the question
Please tell me where he is
Could you tell me why the train is late