2 sentences for 逞强 (chěng​qiáng)

1. 他总爱在女孩子面前逞强。

   tā zǒng ài zài nǚ hái​zi miàn​qián chěng​qiáng.

   He always likes to act tough in front of girls.

   Source: Dong Chinese Dictionary

2. 病还没好，就别逞强去干重活儿。

   bìng hái méi hǎo, jiù bié chěng​qiáng qù gàn zhòng huó​r.

   Since you haven't recovered yet, don't push yourself to do heavy work.

   Source: Dong Chinese Dictionary