1. an act of making something longer or larger
延長；擴大；擴展
They applied for an extension of their visa.
他們申請了簽證的延期。
The company announced the extension of its product line.
該公司宣布擴展其產品線。
Extension Meaning（定義、用法、例句與發音）
extension
noun
快速理解
What does "Extension" mean?What are 2-3 core uses of "Extension"?
「extension」主要指時間或空間上的延長，也指電話分機或電腦檔案格式。
- 1
時間或空間的延長
EN: an act of making something longer or larger
翻譯: 指延長時間、空間或範圍的行為或結果。
- 2
電話分機
EN: an extra telephone connected to the main line
翻譯: 連接至主電話線路的額外電話機或分機號碼。
- 3
電腦檔案的副檔名
EN: a part added to a filename to indicate its format
翻譯: 附加在檔案名稱後的部分，用以標示檔案格式，例如「.doc」或「.jpg」。
- 4
大學的推廣教育
EN: university programs for part-time or adult students
翻譯: 大學為在職或成人學生提供的推廣教育課程或部門。
小提醒：注意「extension」在科技領域常指「副檔名」，而在日常對話中更常指「延長」或「分機」，需根據上下文判斷。
發音（How to Pronounce "Extension" in English）
How to pronounce "Extension" in English?"Extension" US vs UK pronunciation
點擊下方的 US / UK 按鈕可播放發音。
Real-life Examples of "Extension" from YouTube Videos
Why Should I Start a Startup? by Michael Seibel
Y Combinator
“the other kind of question I asked, which is an extension of this, is like, if I think about the moments where I outperform- so not only was I released from than one of it, but actually like delivered the best results, I did the best- where does that happen, mmm?”
(1 out of 20)
Definitions（定義）
What are the definitions of "Extension"?How does "Extension" change by context?
2. an extra part added to something to make it longer
延伸部分；擴建部分
They built an extension to their house.
他們為房子加建了一個延伸部分。
The table comes with two extensions for larger gatherings.
這張桌子配有兩塊延伸板，可供更多人使用。
3. an extra telephone line connected to a central system in a building
電話分機
Please dial extension 345 to reach the sales department.
請撥分機 345 聯繫銷售部門。
My office phone number is 1234, extension 567.
我辦公室的電話號碼是 1234，分機 567。
4. a part that is added to a document to provide extra information
（文件的）附件；附錄
The contract includes several extensions detailing the terms.
這份合同包含幾份詳細說明條款的附件。
See the extension at the end of the report for the full data set.
完整的數據集請參見報告末尾的附錄。
5. the action of reaching or stretching out a part of the body
（身體部位的）伸展，延伸
A good warm-up includes the extension of all major muscle groups.
良好的熱身運動包括伸展所有主要肌肉群。
The dancer's graceful arm extension was impressive.
舞者優雅的手臂伸展令人印象深刻。
Grammar & Patterns（句型）
What are common sentence patterns for "Extension"?How to make natural sentences with "Extension"?
| Pattern | Meaning | Example |
|---|---|---|
| extension + of + noun | ...的延伸 | The new wing is an extension of the main building. (新側翼是主建築的延伸。) |
| extension + to + noun | 對...的擴建 | They are planning an extension to the library. (他們正計劃對圖書館進行擴建。) |
| by extension | 引申而言；推而廣之 | He criticized the policy and, by extension, the government itself. (他批評了這項政策，引申而言，也批評了政府本身。) |
| ask for an extension | 要求延期 | The student asked for an extension on the deadline. (這名學生要求延長截止日期。) |
| file extension | 檔案副檔名 | Make sure you save the document with the correct file extension. (請確保以正確的檔案副檔名儲存文件。) |
用法說明
How is "Extension" different from similar structures?What usage mistakes are common with "Extension"?
extension of vs extension to
- extension of 通常用於表示某物的物理或概念上的延長、擴大，強調是原有事物的延伸部分。
- extension to 則常用於表示對某個建築物、系統或期限的「增建」或「延長」，強調是外加的、附加的部分。
- 在表示「電話分機」時，固定使用 extension，後面不加介系詞，例如 "Dial extension 456."。
對比例句： EN: The new wing is an extension of the main hospital building. 翻譯: 新建的側翼是主醫院大樓的延伸。
EN:We are planning an extension to our house for a home office.
翻譯:我們正計劃為房子增建一個家庭辦公室。
總結建議
一般來說，表示「...的延伸」用 extension of，表示「對...的增建/延長」則用 extension to。
易混淆對比
What is the difference between "Extension" and similar words?How to choose "Extension" vs alternatives?
extension vs expansion
「extension」通常指在原有基礎上延伸或延長，強調線性或範圍的延展；「expansion」則指體積、規模或範圍的擴大，強調向四面八方擴張。
extension vs prolongation
「extension」可指空間或範圍的延伸，也可指時間的延長；「prolongation」則專注於時間的延長，且常帶有刻意延遲或超出預期的意味。
extension vs supplement
「extension」指主體的延伸或擴充，與原主體緊密相連；「supplement」指額外的補充物，用以增強或完善主體，但本身可獨立存在。
口語用法
How is "Extension" used in spoken English?What is the spoken vs formal difference for "Extension"?
引述
在對話中，當引述或轉述他人提出的延長請求或提議時，常用 "extension" 來簡潔地傳達核心概念。 EN: She asked for an extension on the project deadline. 翻譯: 她請求延長專案的截止日期。
EN:So you're saying the boss agreed to an extension?
翻譯:所以你是說老闆同意延期了？
語氣強調
在口語中，會透過重音或語調強調 "extension"，以凸顯延長期限、合約或服務的重要性或意外性。 EN: They gave us a SIX-MONTH extension! 翻譯: 他們給了我們六個月的延長期！
EN:I can't believe there's no extension option.
翻譯:真不敢相信竟然沒有延長選項。
停頓填充
在思考或組織語句時，有時會用 "...an extension..." 作為填充詞，特別是在討論時間、期限或技術細節的場景。 EN: We might need... an extension... to finalize the details. 翻譯: 我們可能需要…延長一下…來敲定細節。
EN:The solution is to get, um, an extension on the warranty.
翻譯:解決辦法就是去取得，嗯，保固的延長。
正式書寫提示：在正式書寫（如學術論文、商業報告、法律文件）中，應避免使用口語中的停頓填充或過於隨意的引述方式。請使用完整、結構清晰的句子來明確說明延長的主體、期限與理由，例如："A two-week extension of the submission deadline was formally requested and subsequently granted."
常見短語
What common collocations use "Extension"?What fixed phrases with "Extension" should I remember?
extension of
extension of [something]
某事物的延伸、擴展或延長
file extension
[file] extension
檔案副檔名（如 .txt, .jpg）
ask for an extension
ask for/request/grant an extension
請求延長期限
hair extension
hair extension(s)
接髮；假髮片
by extension
by extension
推而廣之；由此延伸
extension cord
extension cord/cable
延長線
university extension
university/college extension
大學推廣教育；進修部
常見錯誤
What are common mistakes with "Extension"?Which "Extension" sentences look correct but are wrong?
×I need an extension of my visa.
✓I need an extension on my visa.
對於文件、期限或合約的延長，通常使用介系詞 'on' 或 'to'，而非 'of'。'Extension of' 通常用於指實體的延伸部分或概念的擴展。
×The file extension is .doc.
✓The file extension is .doc.
此為正確用法，但學習者常誤解 'extension' 在此指『副檔名』，而誤用其他詞彙如 'format' 或 'type'。在電腦術語中，'file extension' 是固定說法。
×Can I have an extension for submitting my homework?
✓Can I have an extension to submit my homework?
請求延長期限以完成某事時，常用句型是 'an extension to + verb' 或 'an extension on + noun'。使用 'for + verb-ing' 在此情境下較不自然。
×They are building a new extension of the highway.
✓They are building a new extension to the highway.
指道路、鐵路、線路等具體事物的延伸段時，通常使用介系詞 'to'。'Extension of' 在此情境下可能暗示是原有高速公路的一部分屬性延伸，而非新增一段。
×The phone's extension number is 1234.
✓The phone extension is 1234.
在商業或機構環境中，'extension' 本身已指分機號碼，無需重複 'number'。直接說 'extension 1234' 或 'extension number 1234' 雖可接受，但前者更簡潔常用。
×This program is an extension from the previous version.
✓This program is an extension of the previous version.
表示某事物是另一事物的擴展、發展或延續時，應使用 'extension of'。'Extension from' 在此語意下不正確。
詞形變化
What are the word forms of "Extension"?What are tense/participle forms of "Extension"?