例如第一个习惯用语down and dirty中的dirty就解释为“不正当的, 卑鄙的”，而down在这儿的意思是下流阴险的。所以down and dirty表示的意思类似于dirty pool和shady deal, 都指正派人不屑于做的卑鄙勾当。
例句-1：This guy ran a real down and dirtycampaign; every day he started more rumors about our man’s honesty and personal life. But the voters saw he was lying so we easily beat him.
这家伙为了赢得竞选真是不择手段。他每天都散布谣言中伤我们候选人的品德和私生活。好在选民看透了他在撒谎，所以我们轻而易举就把他击败了。
我们要学的第二个习惯用语是: dirty crack。Crack可以解释为俏皮话或者幽默的玩笑, 但是前面加上dirty意思可就不同了，dirty crack是“刺伤人的`挖苦话”。
例句-2：Finally Bob made a dirty crack about the quarterback -- he called him so dumb he couldn’t add up two and two. At this the man next to him got up and hit him in the eye: it turns out the quarterback was his son.
鲍勃终于忍无可忍了，对着那名四分卫叫喊说，他笨得连二加二是多少都算不出来。他身边那人听了这话站起身来就朝着鲍勃的眼睛打了一拳——原来那名四分卫正是他的宝贝儿子。
