I bet you were a little devil when you were younger.
我敢说你年轻一点的时候是个小淘气鬼。
My niece is a little devil.
我的侄女是个调皮鬼。
The leader seemed the devil incarnate.
那个首领好像是魔鬼的化身。
Go on, be a devil, buy both of them.
来，怕什么，两个都买了吧！
I've had a devil of a job finding you.
我费了九牛二虎之力才找到你。