內(nèi)容簡(jiǎn)介

引導(dǎo)詞 “if” 既可以表示 “如果”，也可以表示 “是否”。在表示 “是否” 的意思時(shí)，有時(shí) “if” 和 “whether” 可以互換使用。這就難倒了一些英語(yǔ)學(xué)習(xí)者 —— 什么時(shí)候該用 “if”？什么時(shí)候該用 “whether”？主持人 Sam 總結(jié)了兩個(gè)規(guī)則，幫助你判斷到底是用 “if” 還是 “whether”，看視頻。

文字稿

When do we use if and when do we use whether? Let's take a look.

The simple rule is that with conditional sentences we use if, and when we have two options, we use whether.

If I get hungry, I'll have a snack.
But I don't know whether to have an apple or a biscuit.

When asking an indirect yes/no question, we can use either if or whether – both are correct.

Do you know if the apples are fresh?
Do you know whether the biscuits are any good?

Whether is maybe a little bit more formal, but with both questions there are only two possible answers – yes or no.

用法總結(jié)

1. 條件句中，用 “if” 表示 “如果”, 不能用 “whether”。

• If I get hungry, I'll have a snack.
• I'll take an umbrella if it rains.

2. 陳述句中提及兩種選擇時(shí)，常用 “whether”。

• I don't know whether to have an apple or a biscuit.
• I can't decide whether to go home or not.

3. 間接一般疑問(wèn)句中，“if” 和 “whether” 都適用，同樣表示 “是否” 的意思。“Whether” 更正式一點(diǎn)。

• Do you know if the apples are fresh?
• Do you know whether the biscuits are any good?
• Can you tell if it's going to rain today?
• Can you tell whether it's going to rain today?