which
which — 限定詞
1. used in questions when you are asking someone to pick one person or thing from a
哪個
從有限選項中提問
used in questions when you are asking someone to pick one person or thing from a limited number of possibilities
Which flavor do you want — chocolate or vanilla?
你想要哪種口味，巧克力還是香草？
which + noun in a choice question
Jude asked the librarian which book the class should read first.
Jude 問圖書館員班上應該先讀哪一本書。
indirect question after asked
Which bus goes to the train station from here?
從這裡到火車站要搭哪一班公車？
The travel agent asked Henrik which dates worked best for his vacation.
旅行社人員問 Henrik 他的假期安排在哪些日期最合適。
- what
Used when the set of possible answers is open, not limited — e.g., 'What book are you reading?' (any book), vs. 'Which book…?' (from a known set).
文法句型
which + noun + (modal) + verb
用法筆記
The answer is expected to come from a set of known options — unlike 'what', which is used when the options are open or unknown. Frequently used with 'of' (which of the…).
常見錯誤
2. used to make clear or ask about the exact identity of a particular person or thi
哪一個；哪個
指明確切的人事物
used to make clear or ask about the exact identity of a particular person or thing among several
Rin showed the new student which desk was hers.
Rin 告訴新同學哪張書桌是她的。
show + which + noun + clause
The doctor asked the nurse which arm the patient had injured.
醫生問護士病人的是哪一隻手臂受傷。
ask + which + noun in embedded question
I cannot remember which street leads to the old market.
我記不起來哪一條路通向舊市場。
Eshe checked the timetable to see which train left before 8 a.m.
Eshe 查看時刻表，想知道哪一班列車在早上八點前出發。
- which one
Used as a pronoun instead of a determiner — e.g., 'I know which one she picked' vs. 'I know which dress she picked.'
文法句型
know/say/see/remember + which + noun + clause
用法筆記
Common after verbs of knowing, showing, telling, and deciding. Unlike sense 1 (direct question), this sense often appears in statements or indirect questions where the speaker is identifying rather than asking.
常見錯誤
3. used after a preposition to connect a clause that gives extra information about
該情況
介繫詞後引導補充資訊
used after a preposition to connect a clause that gives extra information about a time, event, or thing just mentioned in the previous clause
The storm lasted all night, during which time the power went out twice.
暴風雨持續了整晚，期間停電了兩次。
during which time — formal relative determiner
Walid studied in Taiwan for three years, after which period he returned home.
Walid 在台灣學習了三年，之後他便返鄉了。
after which period — linking time phrase
The company lost its main client, as a result of which event half the staff were let go.
公司失去了主要客戶，結果半數員工遭到裁員。
Daichi paid the deposit on Monday, by which date the discount was still available.
Daichi 在星期一付了訂金，那時折扣仍然有效。
文法句型
preposition + which + noun + clause
用法筆記
Frequently used in formal or written English. The preposition (during, after, before, by, in, on, at, for, as a result of) comes before 'which', and together they modify the noun that follows. In informal speech, this construction is often replaced with simpler structures.
常見錯誤
which — 代名詞
1. used in questions when you are asking someone to choose one or more people or th
哪一個
代名詞用法提問選項
used in questions when you are asking someone to choose one or more people or things from a limited set, without repeating the noun
Which of these jackets do you think would be warmer for a snowy day?
你覺得這些外套裡面哪一件在下雪天會比較保暖？
which + of + [group] expanded question
Asher has three cousins, but I cannot guess which is the eldest.
Asher 有三個表兄弟姊妹，但我猜不出誰年紀最大。
Which would you like to drink — juice or tea?
你想喝哪一種，果汁還是茶？
The taxi driver asked which of the two addresses was our final stop.
計程車司機問兩個地址當中哪一個是我們的最終目的地。
- what
'What' is used for open-ended choices — 'What do you want to eat?' (no limit) vs. 'Which do you want?' (from a limited menu).
文法句型
which + of + group noun / pronoun
用法筆記
Unlike the determiner sense (which + noun), this pronoun sense stands alone as the subject or object. It is almost always used with a limited set that is clear from context or introduced by 'of'.
常見錯誤
2. used as the subject or object of a relative clause to refer back to a thing, ani
⋯的；該事物
關係代名詞指代前文事物
used as the subject or object of a relative clause to refer back to a thing, animal, or idea already mentioned, adding more information about it
The movie, which Ramón had already seen twice, was still exciting.
那部電影 Ramón 已經看過兩次了，但還是覺得很精彩。
noun + comma + which + non-restrictive clause
Linh's old bicycle, which she had owned since high school, finally broke down.
Linh 的舊腳踏車是她從高中騎到現在的，最後終於壞了。
The report which Pim wrote in one night won the company award.
Pim 在一夜之間寫出來的那份報告贏得了公司獎項。
The package arrived in a box which was much bigger than the item inside.
包裹送到時裝在一個遠比物品還大的盒子裡。
- that
Can replace 'which' in restrictive clauses (no commas) — 'the book that I read' vs. 'the book which I read.' In non-restrictive clauses, 'that' is informal in British English and incorrect in American English.
文法句型
noun + which + relative clause
用法筆記
For people, 'who' or 'whom' is preferred over 'which'. 'That' can replace 'which' in restrictive (no comma) relative clauses, but not in non-restrictive (with comma) clauses. 'Which' refers to the immediately preceding noun, not to the whole clause — for clause reference, see the determiner relative sense.
常見錯誤
3. used in the pattern 'which is which' when talking about being able to see or exp
哪個是哪個
區分相似事物的固定說法
used in the pattern 'which is which' when talking about being able to see or explain the difference between two or more similar people or things
The twins look so alike that nobody can tell which is which.
那對雙胞胎長得太像了，沒有人分得出來哪個是哪個。
tell which is which — fixed idiom for distinguishing
The teacher mixed up the test papers and could not tell which was which anymore.
老師把考卷弄混了，再也分不清哪一份是哪一份。
All the keys on the desk look identical, so Christopher marked them to know which is which.
桌上所有的鑰匙看起來一模一樣，所以 Christopher 在上面做了記號好知道哪把是哪把。
The wine bottles had no labels, so the waiter could not tell which was which before serving.
那些酒瓶沒有標籤，所以服務生在倒酒前分不清哪瓶是哪瓶。
文法句型
tell/know + which + is + which
用法筆記
The phrase 'which is which' is the most common form and is a fixed expression. The first 'which' refers to one set of items, the second 'which' to the other set. This sense is very common in everyday speech when items are nearly identical.
常見錯誤
which — 形容詞
1. any one that; no matter which one — used before a noun to say that the choice do
任一個
不管哪一個都行
any one that; no matter which one — used before a noun to say that the choice does not matter
Take which seat you want — they are all free.
你想坐哪個位子都可以——全部都是空的。
which + noun + clause = whichever, any that
Jabari told his guests to take which room they preferred for the night.
Jabari 告訴客人們可以任意選擇喜歡的房間過夜。
Choose which route you like best for the weekend hike.
週末健行的路線你喜歡哪條就選哪條。
The children were told they could pick which game they wanted to play first.
孩子們被告知可以先挑選任何一種他們想玩的遊戲。
- whichever
The modern, more natural alternative to this sense — 'Take whichever book you like' is more common than 'Take which book you like.'
文法句型
which + noun + verb (any that…)
用法筆記
This sense is less common in modern everyday speech, where 'whichever' is more typical. It survives in formal or literary styles. The clause after 'which' acts like a free relative, giving the listener full freedom of choice.