You do that, and this tank's gonna get filthier and filthier by the minute.

你那样做的话，这个鱼缸每分钟都会变得越来越脏。

His hands became filthier from the sludge. Having rubbed his hands against his clothes several times he jumped down and walked up to me.

他那时的手更黑了，他把脏手在衣服上擦了又擦，然后跳到地上走了过来。