I bet you were a little devil when you were younger.

　　我敢說你年輕一點的時候是個小淘氣鬼。

　　My niece is a little devil.

　　我的侄女是個調皮鬼。

　　The leader seemed the devil incarnate.

　　那個首領好像是魔鬼的化身。

　　Go on, be a devil, buy both of them.

　　來，怕什么，兩個都買了吧！

　　I've had a devil of a job finding you.

　　我費了九牛二虎之力才找到你。