2 sentences for 张口 (zhāng​kǒu — start talking)

1. 我实在不好意思向他张口借钱。

   wǒ shí​zài bù​hǎo​yì​si xiàng tā zhāng​kǒu jiè qián.

   I'm really embarrassed to ask him for a loan.

   Source: Dong Chinese Dictionary

2. 他张口就是一个屌字，太没礼貌了。

   tā zhāng​kǒu jiù shì yī gè diǎo zì, tài méi lǐ​mào le.

   He blurted out a swear word; it was so rude.

   Source: Dong Chinese Dictionary