1. to do something
做某事，行動
We must act quickly to solve this problem.
我們必須迅速行動來解決這個問題。
He acted without thinking about the consequences.
他沒有考慮後果就行動了。
Act Meaning（定義、用法、例句與發音）
act
verb
快速理解
What does "Act" mean?What are 2-3 core uses of "Act"?
「act」主要指做出行為、扮演角色或發揮功能。
- 1
採取行動
EN: to do something or take action
翻譯: 採取行動、做出行為
- 2
扮演角色
EN: to perform a role in a play, film, etc.
翻譯: （在戲劇、電影等中）扮演角色、表演
- 3
發揮作用
EN: to function or serve as something
翻譯: 發揮作用、充當
- 4
假裝
EN: to behave in a way that is not genuine
翻譯: 假裝、裝作
小提醒：注意「act」作名詞時也很常見，意思是「行為」或「（戲劇的）一幕」。
發音（How to Pronounce "Act" in English）
How to pronounce "Act" in English?"Act" US vs UK pronunciation
點擊下方的 US / UK 按鈕可播放發音。
Real-life Examples of "Act" from YouTube Videos
Hiring Tips from Pebble Watch Founder Eric Migicovsky
Y Combinator
“and at the beginning and at the early stages it's rare to see an employee who can act or work only in one aspect of the business.”
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Definitions（定義）
What are the definitions of "Act"?How does "Act" change by context?
2. to behave in a particular way
表現出某種行為，舉止
She acted surprised when she heard the news.
她聽到消息時表現得很驚訝。
You're acting like a child.
你的行為像個小孩。
3. to perform a role in a play, film, etc.
（在戲劇、電影等中）扮演角色，表演
He acted the part of Hamlet in the school play.
他在學校的戲劇中飾演哈姆雷特。
She has acted in several television dramas.
她曾在好幾部電視劇中演出。
4. to have an effect or function
起作用，產生效果
This medicine acts as a painkiller.
這種藥有止痛的作用。
The chemical acts on the nervous system.
這種化學物質作用於神經系統。
5. to pretend or feign
假裝，裝作
He's not really angry; he's just acting.
他不是真的生氣，只是在裝樣子。
She acted as if nothing had happened.
她裝作什麼事都沒發生過。
Grammar & Patterns（句型）
What are common sentence patterns for "Act"?How to make natural sentences with "Act"?
| Pattern | Meaning | Example |
|---|---|---|
| act + adverb | 以某種方式行動 | He acted quickly in the emergency. (他在緊急情況下迅速行動。) |
| act + as + noun | 擔任、充當 | She will act as the team leader. (她將擔任團隊領導。) |
| act + on/upon + noun | 根據…行動 | The police must act on the information. (警方必須根據情報採取行動。) |
| act + for/on behalf of + noun | 代表…行事 | The lawyer is acting for the defendant. (律師正代表被告行事。) |
| act + like + noun | 行為像… | Don't act like a child. (別像個孩子一樣行事。) |
| act + out + noun | 表演出來、將…付諸行動 | The children acted out the story. (孩子們把故事表演了出來。) |
| act + against + noun | 違反、對抗 | This decision acts against our principles. (這項決定違背了我們的原則。) |
| act + to + verb | 採取行動以… | The government acted to stabilize the market. (政府採取行動以穩定市場。) |
用法說明
How is "Act" different from similar structures?What usage mistakes are common with "Act"?
act as vs act like
- act as 表示「擔任、充當」某個正式或功能性的角色，強調實際的職責或功能。
- act like 表示「行為舉止像…」，強調模仿某種特質、行為或狀態，通常帶有比較或比喻的意味。
- 當後接名詞時，
act as後的名詞前常省略冠詞（如act as manager），而act like後的名詞則通常需要冠詞或限定詞（如act like a child）。
對比例句： EN: She will act as the team leader during the project. 翻譯: 在專案期間，她將擔任團隊領導。
EN:He acts like a spoiled child when he doesn't get his way.
翻譯:當他不順心時，行為舉止就像個被寵壞的孩子。
總結建議
在表示擔任職務或發揮功能時用 act as，描述行為相似或比喻時則用 act like。
易混淆對比
What is the difference between "Act" and similar words?How to choose "Act" vs alternatives?
act vs behave
「act」強調具體的動作或表演，而「behave」強調行為舉止是否符合規範或禮儀。
act vs perform
「act」側重於扮演角色或採取行動，而「perform」強調執行一項任務、職責或公開演出。
act vs pretend
「act」可以是真實或假裝的行為，而「pretend」明確指假裝或虛構。
口語用法
How is "Act" used in spoken English?What is the spoken vs formal difference for "Act"?
引述
在轉述他人說過的話或想法時，常用來引出行為或決定。 EN: He was like, "I need to act now or it'll be too late." 翻譯: 他當時就說：「我必須現在就行動，否則就太遲了。」
EN:She told me, "Just act natural and everything will be fine."
翻譯:她告訴我：「只要表現得自然一點，一切都會沒事的。」
語氣強調
在口語中，常與副詞連用，以強調行為的特定方式或即時性。 EN: You have to act fast if you want to secure the deal. 翻譯: 如果你想拿下這筆交易，就必須迅速行動。
EN:Don't just stand there—act!
翻譯:別只是站在那裡——快行動啊！
停頓填充
在思考或組織語句時，用作短暫的停頓填充詞，引出後續的動作或計畫。 EN: So I was thinking... act... maybe we should call them first. 翻譯: 所以我當時在想… 那個… 或許我們應該先打給他們。
EN:What we need to do is, act, form a proper strategy.
翻譯:我們需要做的是，嗯，制定一個完善的策略。
正式寫作注意：上述口語用法（尤其是「停頓填充」和隨意的「引述」結構）在正式書面報告、學術論文或商業文件中應避免使用，請改用更精確、結構完整的表達方式。
常見短語
What common collocations use "Act"?What fixed phrases with "Act" should I remember?
act as
act as [noun]
擔任；充當；起…的作用
act on
act on [noun/advice]
根據…行動；對…起作用
act up
act up
（機器）出故障；（人）調皮搗蛋
act out
act out [something]
表演出來；將（情緒、幻想）付諸行動
act accordingly
act accordingly
據此行動；採取相應行動
act in good faith
act in good faith
善意行事；真誠行事
act the part
act the part
演得像；舉止符合（某種角色或形象）
常見錯誤
What are common mistakes with "Act"?Which "Act" sentences look correct but are wrong?
×We need to take an immediate act.
✓We need to take immediate action.
"Act" 作為名詞時，通常指具體的單一行為或舉動；而 "action" 則更常指需要採取的行動、行動過程或一系列行為。在 "take an..." 的搭配中，通常使用 "action"。
×He acted like a mediator in the meeting.
✓He acted as a mediator in the meeting.
"Act as" 表示正式擔任某個角色或職務；"act like" 表示行為舉止像某種人或物，但並非正式擔任該角色。
×We must act immediately to solve the crisis.
✓We must act immediately to solve the crisis.
此句原為正確，但學習者常誤以為 "act" 後必須直接接名詞，而省略表達目的的 "to + 動詞" 結構。"Act" 作為動詞時，常與 "to + 動詞" 連用，表示行動的目的。
×A new law was acted by the parliament.
✓A new law was passed by the parliament.
"Act" 作為「制定法律」的意思時，是及物動詞，主語通常是立法機構（如 parliament, congress）。法律本身是「被通過」，應使用 "pass a law" 或 "enact a law"。"Act" 在此語境下不用於被動語態表示法律被制定。
×You need to act different in a professional setting.
✓You need to act differently in a professional setting.
修飾動詞 "act" 應該使用副詞 "differently"，而非形容詞 "different"。這是常見的形容詞與副詞混淆錯誤。
×We should act for his advice.
✓We should act on his advice.
"Act on something" 表示依據某資訊、建議或指示採取行動；"act for someone" 則表示代表某人行事（如律師代表客戶）。兩者介系詞不同，意思也不同。
詞形變化
What are the word forms of "Act"?What are tense/participle forms of "Act"?
acts(3rd_singular)acting(present_participle)acted(past)acted(past_participle)