这块木头经过处理后变得很坚硬。

Zhè kuài mùtou jīngguò chǔlǐ hòu biàn dé hěn jiānyìng.

This piece of wood becomes very hard after processing.

这个材料的质地非常坚硬耐用。

Zhège cáiliào de zhìdì fēicháng jiānyìng nàiyòng.

The texture of this material is very hard and durable.

这把刀的刀刃非常坚硬锋利。

Zhè bǎ dāo de dāo rèn fēicháng jiānyìng fēnglì.

The blade of this knife is very hard and sharp.