whether
/ˈhweðə(r)/conjunction
1- expressing a doubt or choice between alternatives是…（还是）; 或者…（或者）; 不是…（就是）：
he seemed undecided whether to go or stay
他似乎不能决定是走还是留
it is still not clear whether or not he realizes.
他是否意识到了还不清楚。
1.1
- expressing an enquiry or investigation (often used in indirect questions)是否（表示询问或调查, 常用于间接引语中）：
I'll see whether she's at home.
我去看看她是否在家。
1.2
- indicating that a statement applies whichever of the alternatives mentioned is the case无论如何, 不管怎样：
I'm going whether you like it or not.
不管你喜欢与否, 我都要走。
USAGE
On the difference between whether and if, see usage at IF.
短语
whether or no
1
- whether or not是否：
the only issue arising would be whether or no the publication was defamatory.
惟一产生的问题是确定该出版物是否是诽谤性的。
2
- archaic in any case〈古〉无论如何, 不管怎样：
God help us, whether or no!
不管怎样, 愿上帝能帮助我们。
词源
Old English hw æther, hwether, of Germanic origin; related to German weder 'neither'.