Correct
开口子
/ kāikǒuzi /
Strokes
Definition
a dike breaks/fig. to provide facilities (for evil deeds)/to open the floodgates
Example
As a Verb
(of a dyke) break; burst; breach the dam
1
Hédī
河堤
zuówǎn
昨晚
kāikǒuzi
开口子
le
了
。
The dyke broke/burst last night.
As a Verb
break a rule; set a bad precedent; grant/make an exception
2
Nǐ
你
zhège
这个
kǒuzi
口子
wǒ
我
bù
不
néng
能
kāi
开
。
I can't make an exception in your case.