working myt ass off 此话何解

工作了很多！

严重欺骗
不能用your ass off

因为"my ass off"是固定搭配，没有实际意义，仅仅表示语气的加强
1. my ass off
to do a lot or do way too much
强调做了很多

I have been working my ass off!

2. my ass off
HAS NO MEANING, just a rhythmic expression.
无实际意义，仅用加强语气