expensive

Compared meaning: costing a lot of money (adjective).

比较义项：花费很多钱的、价格高的（adj.）。

• expensive 本词

  The general, neutral word for anything costing a lot; works in any context—goods, services, prices—and any register, from casual talk to formal writing.

  最中性、最常用的词，用来表示任何东西花费很多钱；适用于商品、服务、价格等各种语境，也适用于口语和书面语等各种语域。

  Concert tickets for that band are expensive, often over two hundred dollars.

  那支乐队的演唱会门票很贵，常常要两百多美元。

• costly

  More formal; often stresses a high price as a serious drawback or consequence, especially for repairs, mistakes, or long-term investments, not everyday shopping.

  语气更正式；常强调高价是一种严重的不利后果，尤其用于维修、错误或长期投资，而不是日常购物。

  Delaying the roof repair proved costly once the leak caused serious damage.

  拖延屋顶维修的代价高昂，因为渗水最终造成了严重的损坏。

• dear

  Informal, mainly British usage for something pricier than expected, often in spoken complaints about everyday costs; sounds old-fashioned or regional in American English.

  口语化，主要用于英式英语，指价格比预期更高；常用于对日常花费的口头抱怨，在美式英语中显得过时或带有地方色彩。

  Everything in London feels quite dear compared with prices back home.

  在伦敦，什么东西感觉都相当贵，比家乡的价格高不少。

Expensive, costly and dear all mean costing a lot. Expensive is the general, neutral word for anything costing a lot, in any context. Costly is more formal, stressing high price as a serious drawback, like repairs. Dear is informal British usage, sounding old-fashioned.

这三个词都表示价格高、花费大，但语气和适用场合不同：expensive 最中性、最常用；costly 更正式，常强调高价带来的不利后果；dear 在这个意义上多见于英式英语口语，且用法偏老式。这里不比较 dear 用于书信称呼时表示“亲爱的”的意思（如 Dear friend）。