1. having a high price; expensive
價格高昂的；昂貴的
The repairs to the old house proved to be very costly.
修理這棟老房子的費用證明非常昂貴。
They avoided the costly restaurants in the city center.
他們避開了市中心那些價格高昂的餐廳。
Costly Meaning（定義、用法、例句與發音）
costly
adjective
快速理解
What does "Costly" mean?What are 2-3 core uses of "Costly"?
形容某事物需要付出高昂代價，無論是金錢、時間或其他資源。
- 1
昂貴的
EN: involving a lot of money; expensive
翻譯: 指需要花費大量金錢的。
- 2
代價高的
EN: causing a lot of problems, loss, or damage
翻譯: 指會導致嚴重問題、損失或損害的，後果嚴重。
- 3
耗費巨大的
EN: requiring a great amount of time, effort, or resources
翻譯: 指需要投入大量時間、精力或其他資源的。
小提醒：「costly」不僅指「昂貴的」，更常強調因昂貴或重大而帶來負面後果或犧牲，比「expensive」語氣更強。
發音（How to Pronounce "Costly" in English）
How to pronounce "Costly" in English?"Costly" US vs UK pronunciation
點擊下方的 US / UK 按鈕可播放發音。
Real-life Examples of "Costly" from YouTube Videos
Emily Oster: What do we really know about the spread of AIDS?
TED
“that's a costly investment in your health, But how much you want to invest is going to depend on how much longer you expect to live in the future, even if you don't make those investments.”
(1 out of 7)
Definitions（定義）
What are the definitions of "Costly"?How does "Costly" change by context?
2. causing a lot of problems, loss, or damage
造成許多問題、損失或損害的；代價慘重的
The company made a costly mistake by ignoring market research.
該公司因忽視市場調查而犯下一個代價慘重的錯誤。
The war was a costly victory for both sides.
這場戰爭對雙方來說都是一場代價慘重的勝利。
3. requiring a great amount of time, effort, or resources
耗費大量時間、精力或資源的
Implementing the new security system was a lengthy and costly process.
實施新的安全系統是一個漫長且耗費資源的過程。
Maintaining such a large garden is too costly for them now.
維護這麼大的花園對他們來說現在太耗費精力了。
Grammar & Patterns（句型）
What are common sentence patterns for "Costly"?How to make natural sentences with "Costly"?
| Pattern | Meaning | Example |
|---|---|---|
| costly + noun | 昂貴的… | The company abandoned the costly project. (公司放棄了那個成本高昂的專案。) |
| costly + to + verb | 做…是昂貴/代價高的 | Mistakes like these are costly to fix. (這類錯誤要修正起來代價很高。) |
| prove + costly | 結果證明代價高昂 | His lack of preparation proved costly in the end. (他準備不足最終證明代價慘重。) |
| a costly + mistake/error/victory | 一個代價高昂的錯誤/勝利 | It was a costly victory, with many lives lost. (這是一場代價慘重的勝利，許多人喪生。) |
| too costly + to + verb | 太昂貴以致於無法… | The proposed solution was too costly to implement. (提議的解決方案實施起來成本太高。) |
用法說明
How is "Costly" different from similar structures?What usage mistakes are common with "Costly"?
costly to do vs. costly doing
- costly to do 是最常見的結構，用於描述執行某個特定動作或達成某個目標需要付出高昂代價。
- costly doing 較為少見，通常用於描述某個持續的、習慣性的或泛指的行為本身是昂貴的。
- 在正式寫作或大多數情況下，使用 costly to do 是較為安全且自然的選擇。 EN: It would be costly to repair the entire bridge. 翻譯: 修復整座橋樑將會耗資巨大。
EN:The company avoids costly delaying of product launches.
翻譯:這家公司避免代價高昂的產品發布延遲。
總結建議
建議優先使用 "costly to + 動詞原形" 來表達「做某事成本高昂」，這是最通用且不易出錯的結構。
易混淆對比
What is the difference between "Costly" and similar words?How to choose "Costly" vs alternatives?
costly vs expensive
「costly」強調代價高昂，常包含時間、精力、機會等無形成本；「expensive」主要指金錢價格高。
costly vs pricy
「costly」較正式且涵義更廣；「pricy」較口語，僅指價格高。
costly vs dear
「costly」強調高昂代價；「dear」在英式英語中指價格高，或帶有情感價值。
口語用法
How is "Costly" used in spoken English?What is the spoken vs formal difference for "Costly"?
引述
在口語中，當引述或轉述他人的評價時，常用「costly」來概括，語氣較為客觀。 EN: He said the repairs were too costly, so he decided to sell the car. 翻譯: 他說維修太昂貴了，所以決定把車賣掉。
EN:Everyone agreed it was a costly mistake, but we had to move on.
翻譯:大家都同意那是個代價高昂的錯誤，但我們必須向前看。
語氣強調
在非正式對話中，常與「so」、「really」、「way too」等副詞連用，以加強「昂貴」或「代價大」的語氣。 EN: That vacation was so costly, but totally worth it for the memories. 翻譯: 那次度假花費真高，但為了那些回憶完全值得。
EN:Getting a last-minute ticket is way too costly; let's plan ahead next time.
翻譯:買最後一刻的機票貴太多了，我們下次還是提前計劃吧。
停頓填充
在思考或組織語句時，有時會用「costly...」作為停頓填充，引出後續的解釋或比較。 EN: The project was... costly... but we managed to secure extra funding. 翻譯: 這個專案嘛…代價不菲…但我們設法爭取到了額外資金。
EN:It's a bit costly... you know, compared to the other options on the market.
翻譯:這有點貴…你知道的，跟市場上其他選擇比起來。
注意：在正式書寫或學術報告中，應避免將「costly」用於上述口語停頓或過於隨意的強調結構，建議使用更精確的詞彙如「expensive」、「prohibitively expensive」或「incurred significant costs」。
常見短語
What common collocations use "Costly"?What fixed phrases with "Costly" should I remember?
a costly mistake
adj. + n.
代價高昂的錯誤
a costly error
adj. + n.
代價高昂的失誤
a costly battle
adj. + n.
代價慘重的戰鬥
a costly victory
adj. + n.
代價慘重的勝利
a costly venture
adj. + n.
耗資巨大的事業/投資
costly to maintain
adj. + to-inf.
維護成本高昂
costly in terms of
adj. + prep. phrase
在...方面代價高昂
prove costly
v. + adj.
被證明代價高昂
常見錯誤
What are common mistakes with "Costly"?Which "Costly" sentences look correct but are wrong?
×The repair was very costly expensive.
✓The repair was very costly.
"Costly" already means "expensive" or "involving great cost". Using "costly" and "expensive" together is redundant.
×This bag is more costly than that one.
✓This bag is more expensive than that one.
While "costly" can be used in comparative forms, it is more formal and often describes abstract losses or serious consequences. For direct price comparisons of everyday items, "expensive" is more natural and common.
×It costs costly to maintain the equipment.
✓It is costly to maintain the equipment.
"Costly" is an adjective, not an adverb. It describes nouns (e.g., a costly project) or follows linking verbs like "is", "seems", "became". It cannot modify a verb.
×The war was cost.
✓The war was costly.
"Cost" is primarily a noun or verb. The adjective form is "costly". Learners sometimes mistakenly use the base form "cost" as an adjective.
×He bought a costly priced car.
✓He bought a costly car.
"Costly" inherently implies a high price or cost. Adding "priced" is redundant and unnatural. Use "costly" alone to modify the noun.
×The mistake made a costly result.
✓The mistake had costly consequences.
The collocation "costly result" is uncommon. "Costly" more naturally pairs with words like "mistake", "error", "consequence", "battle", "venture", or "investment" that imply a significant negative outcome or high expenditure.
詞形變化
What are the word forms of "Costly"?What are tense/participle forms of "Costly"?