whether 和 if 用處有何分別?

whether 同 if 其實o係用法上無咩分別
好似although 同though咁..
Please tell me if you know
Please tell me whether you know (or not)
上面位人士講話if多數放o係前面..
其實唔係架囉.. 放o係中間都可以.. 個意思都會相同
whether o個度可以加or not或者唔加都ok
唔加就比較正中d不過中國人就會覺得無咁順口囉

whether 同if都係conjunction，佢地最令人混淆既係當解釋為「是否」時，例如：

我唔知我係唔係鍾意佢
--> I am not sure if I like him.
--> I am not sure whether I like him or not.

呢兩句表達既野都一樣。只係句子結構唔一樣。用 if 後面唔駛or not。用whether唔用or not既話意思就唔完整

[If] is for direct speech, [Whether] is for indirect speech.
E.g. If you like, you can borrow my car.
Mary stopped me whether I was working ......

Hope can help

2006-12-03 19:02:31 補充：
Indirect speech or reporting speech

whether通常用在是否題
通常whether會跟or not一起用
You have to drink 8 glasses of water everyday whether you like or not
無論你喜歡與否~你每日一定要飲8杯水

if=如果
通常和will, can, would, could一起用
If I finish my homework, I will go and see a movie.
如果我做完我的功課~我會去看一場電影