嘴硬 (zuǐyìng) firm in speech; stubborn and reluctant to admit mistakes or defeats

Usage:

“嘴硬”的字面意义是嘴巴很硬。它用来形容心里明白自己错了，但是嘴上却不承认自己的错误。
“嘴硬”literally means a tough mouth. It is used to describe a person who knows his or her own faults, but refuses to admit.

Sentences:

1、Nǐ bié zài zuǐyìng le, gǎnkuài gěi lǎobǎn dào ge qiàn ba, fǒuzé tā huì kāichú nǐ de.
你别再嘴硬了，赶快给老板道个歉吧，否则他会开除你的。
Admit your mistakes and apologize to the boss quickly, or he will fire you.

2、Wǒmen yǐjīng zhǎngwò le zúgòu de zhèngjù, tā zuǐyìng yě méiyǒu yòng.
我们已经掌握了他犯罪的足够证据，他嘴硬也没有用。
It’s useless for him to refuse to admit his guilt, because we have grasped enough evidence.

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