He used his sore finger as a pretext for not going to school.

他口手指疼而不去上学。

That excuse simply won’t wash with me.

那个口我可难以。

She’s always got a thousand and one excuses for everything.

论什么事她都有一大堆口。

He left early on the pretext that he had a bad tootache and had to see the dentist.

"他早退口他牙疼得厉害,得去看牙科医生。"

That's a preposterous excuse!

那一个荒口!