which one的意思是：哪壹個。
which
英 [w?t?] 美 [hw?t?,w?t?]
pron.
哪個;哪壹個;哪壹些;那，指前面提到的事 adj.哪壹個;哪壹些
例句：
questions when there are two or more possible answers or alternatives.
他們想讓我做什麽,宣戰還是投降？
wanted to know which school it was you went to...
我想知道妳上的是哪所學校。
在慌亂中她記不清哪個是格蘭傑先生的船艙。
Which is also a conjunction.In her panic she couldn't remember which was Mr Grainger's cabin...
在慌亂中她記不清哪個是格蘭傑先生的船艙。