4 sentences

1. 艰苦的环境造就了他坚韧不拔的性格。

   jiān​kǔ de huán​jìng zào​jiù le tā jiān​rèn bù bá de xìng​gé.

   The harsh environment forged his resilient character.

   Source: Dong Chinese Dictionary

2. 面对长期的挫折，他展现出了坚韧的意志力。

   miàn​duì cháng​qī de cuò​zhé, tā zhǎn​xiàn chū le jiān​rèn de yì​zhì​lì.

   Facing long-term setbacks, he demonstrated resilient willpower.

   Source: Dong Chinese Dictionary

3. 古代劳动人民常用坚韧的大麻纤维来织布。

   gǔ​dài láo​dòng rén​mín cháng​yòng jiān​rèn de dà​má xiān​wéi lái zhī​bù.

   Ancient laborers often used tough hemp fibers to weave cloth.

   Source: Dong Chinese Dictionary

4. 这种材料既轻便又坚韧，非常适合制作登山绳。

   zhè zhǒng cái​liào jì qīng​biàn yòu jiān​rèn, fēi​cháng shì​hé zhì​zuò dēng​shān​shéng.

   This material is both lightweight and tough, making it ideal for climbing ropes.

   Source: Dong Chinese Dictionary