He always picked the hardest and dirtiest jobs.

他总是挑最脏最累的活干。

But coal is also seen as the dirtiest fuel.

但是煤炭也被看作最肮脏的燃料。

Dirtiest: 1. London 2. Paris 3. Rome, Athens (tied).

最脏乱城市：1.伦敦2.巴黎3.罗马、雅典（并列）

I wouldn't say Stockton was the dirtiest player in the league.

我不认为斯托克顿是联盟最脏的球员。

Who should be held accountable for anti-terrorism’s dirtiest business?

谁该为反恐活动中最肮脏的交易负责？