4 sentences

1. 你的意志力很强。

   nǐ de yì​zhì​lì hěn qiáng.

   You've got a lot of willpower.

   Source: Tatoeba

2. 这次跨省的长途远足是对他意志力的磨炼。

   zhè cì kuà shěng de cháng​tú yuǎn​zú shì duì tā yì​zhì​lì de mó​liàn.

   This long-distance cross-province hike was a test of his willpower.

   Source: Dong Chinese Dictionary

3. 他虽然是个侏儒，但意志力比常人还要坚强。

   tā suī​rán shì gè zhū​rú, dàn yì​zhì​lì bǐ cháng​rén hái yào jiān​qiáng.

   Although he is a dwarf, his willpower is stronger than that of ordinary people.

   Source: Dong Chinese Dictionary

4. 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