hard; stiff; callous; flinty; ironbound; marble; petrosal

1. （打火機用的）電石一種由能產(chǎn)生火星的、堅硬的合金小圓柱體，用于點燃打火機燃料
   A small solid cylinder of a spark-producing alloy, used in lighters to ignite the fuel.
2. 桁架用木棒或金屬棒做成的堅硬的構(gòu)架，用于支撐屋頂等結(jié)構(gòu)
   A rigid framework, as of wooden beams or metal bars, designed to support a structure, such as a roof.
3. 金剛砂是非常堅硬的金屬物質(zhì)。
   The emery is a hard metallic substance.
4. 黑檀樹是一種黑色而堅硬的樹木。
   Ebony is a hard black wood.

堅的英語翻譯：

硬的英語翻譯：