汗流渎背
All of a muck of sweat.
Drenched with sweat.
In a sweat.
Perspire profusely.

eg：We have to carry out such a major project with all of a muck of sweat.

中英俚语俗语来源：后汉书·伏皇后纪：“操去，顾左右，汗流浃背。”