如: 正: Whether it is true or not, I can’t tell. 误: If it is true or not, I can’t tell.
3. whether可以引导带to的不定式。如:
正:I don’t know whether to accept or refuse. 误:I don’t know if to accept or refuse.
• Scientists have proved that the earth
moves around the sun.
其他问题
A)if既能引导条件状语从句,又能引导宾语从 句。因此,遇到它们就要认真分析一下。 如:
• If it rains tomorrow,I won’t come.
(条件状语从句) if表示“如果,要 • I don’t know if it w是il”l rain tomorrow.
• I am sure (that) he will succeed.
2. 由连接代词who, whom, whose, what, which和 连接副词when, where, why引导的宾语从句。这 些连接代词和连接副词在宾语从句中充当某个成 分。例如:
• Do you know who (whom) they are waiting for?
(宾语从句)
if表示“是否”
中考范例
1. (2004年北京市中考试题) Miss Green didn’t tell us _____ in 2002. A. where does she live B. Where she lives C. where did she live D. where she lived 【解析】答案:D。 该题考查的是宾语从句的语序和时态。宾语从句应 用陈述句的语序和时态,所以应选D。