Too much town driving had dirtied the spark plugs .

在市区开车过多，把火花塞弄脏了。

Advice included : " if you use a public toilet and it 's dirty , clean it , otherwise those who come after you will think you dirtied it . "

其中指导建议包括：“要是你上公共厕所，但厕所很脏，那就弄干净它，否则随后进来的人会以为是你弄脏的。”

He never dirtied his hands with political intrigue .

他从不参与政治阴谋玷污自己.

The student dirtied his new books carelessly .

那个学生不小心弄脏了他的新书。

The children dirtied the floor .

孩子们把地板弄脏了。