嘴硬

zhī dào cuò le jiù bié zuǐ yìng le

知道错了，就别嘴硬了。

You know you're wrong, so don't stubbornly insist that you aren't.

nǐ míng xiǎn cuò le jiù bù yào zài zuǐ yìng

你明显错了，就不要再嘴硬。

It's obvious that you are wrong, so don't stubbornly insist that you are not.

tā yī xiàng zuǐ yìng cóng bù rèn cuò

她一向嘴硬，从不认错。

She never says uncle.