why
why — 副詞
1. used when you want to know the cause, purpose, or explanation of an action, even
為什麼
詢問原因或目的的疑問詞
used when you want to know the cause, purpose, or explanation of an action, event, or situation — asking what made something happen or what someone's intention was.
Why did Eitan decide to move back to Japan after living in London for ten years?
為什麼 Eitan 在倫敦住了十年之後，決定搬回日本？
direct question: why + did + subject + verb
Reema asked her brother why he had not called their mother on her birthday.
Reema 問她哥哥，為什麼媽媽生日那天他沒有打電話給她。
reported question: asked + why + subject + verb (normal order)
Why is the library closed on Sunday when so many students want to study there?
為什麼圖書館星期日不開門，明明那麼多學生想在那裡唸書？
Jiwoo could not understand why her application for the scholarship was rejected.
Jiwoo 不明白為什麼她的獎學金申請被拒絕了。
Think our new recycling policy is unfair? Tell me why instead of just shrugging.
覺得我們的新回收政策不公平？直接告訴我為什麼，別只是聳肩。
- how come
informal equivalent used in casual conversation; does not require auxiliary inversion ('How come you left?')
- for what purpose
more formal and specific about intention rather than general cause
文法句型
why + do/does/did + subject + verb?
why + be + subject?
reported: ask/wonder/know + why + subject + verb
用法筆記
In everyday spoken English, 'why' is very frequently used alone as a one-word question after a statement (e.g. 'I am not going.' 'Why?'). It also pairs with 'not' to make suggestions: 'Why not try the new café?'
常見錯誤
why — 連接詞
1. introduces a clause that gives the cause or purpose of an event, explaining what
為何；為什麼
引導說明原因的從句
introduces a clause that gives the cause or purpose of an event, explaining what made it happen or what someone intended — used after verbs like 'know', 'explain', 'understand', and 'ask'.
Christopher explained why he had missed the team meeting — his flight was delayed by six hours.
Christopher 解釋了他為什麼錯過團隊會議——他的班機延誤了六個小時。
explain + why + clause (past perfect)
That is why Kenji always checks the oil level before a long drive.
那就是為什麼 Kenji 在長途開車前總是檢查機油量的原因。
that is why + clause (result structure)
Do you see why Amihan was upset when the school moved her daughter's flute lesson from Tuesday to Saturday morning?
你明白為什麼 Amihan 在學校把她女兒的長笛課從星期二改到星期六早上之後感到不高興了嗎？
The teacher showed the class why water expands when it freezes.
老師向全班同學說明為什麼水結冰時體積會膨脹。
Nobody could figure out why the printer kept jamming every time they used blue paper.
沒有人能搞清楚為什麼每次用藍色紙，那台印表機就卡紙。
- for which reason
more formal; often used in academic or legal writing
- the reason that
interchangeable in most contexts, though 'the reason that' is slightly more explicit
文法句型
know/understand/explain/see + why + clause
that is why + clause
the reason is why + clause
用法筆記
When 'why' introduces an embedded clause (after 'know', 'explain', 'wonder', etc.), the clause keeps normal subject-verb word order — do not use the inverted question structure. Compare: 'Why did she leave?' (direct question) vs. 'I know why she left.' (embedded clause).
常見錯誤
2. used after a noun such as 'reason' or 'cause' to link it to a clause that explai
的緣故
接在reason等名詞後引導說明
used after a noun such as 'reason' or 'cause' to link it to a clause that explains the content of that reason — for example, 'the reason why they left' means 'the reason for which they left'.
The main reason why Élise moved to Berlin was the opportunity to work in film.
Élise 搬到柏林的主要緣故，是為了從事電影工作的機會。
the reason why + clause
There are several reasons why the old bridge needs to be replaced before winter.
有幾個原因可以說明為什麼那座舊橋需要在冬天之前拆除。
The contractor listed the main reasons why the roof replacement took longer than planned.
承包商列出了屋頂更換工程比原訂計畫耗時更久的主要原因。
Can you think of any reason why the bank should not approve Mr. Kim's loan application for the new restaurant?
你能想出銀行不應該批准 Kim 先生那間新餐廳的貸款申請的任何理由嗎？
One reason why Justin enjoys teaching is that he loves watching students discover new ideas.
Justin 喜歡教學的一個緣故，是他很愛看學生發現新想法時的眼神。
- for which
the formal equivalent; 'the reason for which they left' is more formal and less common in speech
文法句型
the reason why + clause
the reasons why + clause
(a/the) cause why + clause
用法筆記
Some traditional style guides discourage 'the reason why' as redundant ('reason' already contains the idea of 'why'), but this construction is extremely common in both spoken and written English at all levels, and most modern dictionaries accept it as standard. Removing 'why' ('the reason they left') produces a cleaner style that is also correct.
常見錯誤
why — 感嘆詞
1. said at the beginning of a sentence to show that you are surprised, mildly annoy
哎呀；咦
表示驚訝、惱怒或恍然大悟
said at the beginning of a sentence to show that you are surprised, mildly annoyed, or have just suddenly understood something that you had not noticed before.
Why, if it is not young Cyrus! I hardly recognised you with that beard.
哎呀，這不是小 Cyrus 嗎！你留了鬍子，我差點認不出來。
surprise at recognising someone
Why, that was exactly what Dr. Nakamura told me to do — take a short walk every hour.
哎呀，那正是 Nakamura 醫生叫我做的事——每小時起來走一小段路。
Why, I have been waiting for this bus for almost forty minutes — this is ridiculous!
哎呀，我在這裡等公車等了快四十分鐘——這也太誇張了吧！
Why, I never expected to find Hiro at a tango festival — he told me he hated dancing.
哎呀，我從沒想過會在探戈節上看到 Hiro——他跟我說過他討厭跳舞。
文法句型
Why, + full sentence
Why, + fragment (noun phrase)
用法筆記
This exclamation is heard less often in modern everyday speech than in older English or in literature. Younger speakers are more likely to use 'Oh!' or 'Hey!' to express the same feeling. However, it remains common in some regional varieties of English and in formal writing meant to sound dramatic or old-fashioned.
常見錯誤
why — 名詞
1. the causes, explanations, or reasoning that lie behind an action, decision, or s
原因；理由
事情發生的緣由和細節
the causes, explanations, or reasoning that lie behind an action, decision, or situation — appearing almost always as part of the set phrase whys and wherefores, which refers to the full set of reasons and background details.
The report explained all the whys and wherefores of the company's decision to close three factories.
那份報告說明了公司決定關閉三家工廠的所有原因與細節。
fixed phrase: the whys and wherefores [+ of]
Before you criticise the new hospital budget, learn the whys and wherefores behind each cut.
在你批評醫院的新預算之前，先了解每項削減背後的原因與來龍去脈。
Zola did not care about the whys and wherefores — she just wanted the problem fixed by Friday.
Zola 不在乎那些原因與細節——她只希望在星期五之前把問題解決。
Before the company holiday party, Emre wanted to understand the why behind each sudden rule change the HR team announced.
在公司年終派對之前，Emre 想了解人資團隊宣布的每一項臨時規則變更背後的原因。
文法句型
the whys and wherefores of + noun phrase
the why behind + noun phrase
用法筆記
The plural expression 'the whys and wherefores' is by far the most common form of this noun sense. Using 'why' as a standalone countable noun ('the why behind something') is a more recent, informal development often seen in business and self-development writing.