pron. Which (of two); which one (of two); -- used
interrogatively and relatively.
conj. In case; if; -- used to introduce the first or two or
more alternative clauses, the other or others being connected by or, or
by or whether. When the second of two alternatives is the simple
negative of the first it is sometimes only indicated by the particle
not or no after the correlative, and sometimes it is omitted entirely
as being distinctly implied in the whether of the first.
conj. 是否, 不论
pron. 两个中的哪一个
1. I don't know whether to go to the party or stay home.
我不知道是去参加聚会还是待在家里。
2. She asked whether I wanted tea or coffee.
她问我想要茶还是咖啡。
3. We need to decide whether we will travel this summer.
我们需要决定这个夏天是否去旅行。