1樓：
you'll never know how hard it is if you've never done this job by yourself.
2樓：匿名使用者
you would never know the hardness of this work without trying in person.
3樓：匿名使用者
if you never tried it, you will never know how tough this work is.
4樓：匿名使用者
didn't engage in this work personally , you don't know the hard
5樓：匿名使用者
not personally engaged in this work, you don't know the hard