例句：
1.ugly： Life had sad, even ugly facts .人生是有一些悲哀的、甚至丑恶的'事实。
2.unable ： I am unable to keep my engagement with you .我不能和你们朝夕相处。
3.uncertain：Faith is an uncertain relief . 信仰实在是一种解救,虽然看来有点渺茫。
4.uncle：Immy is uncle to all the kids who like to go boating with him. 那些喜欢和吉米一起乘船游玩的孩子都把他当叔叔
5.under:Do you think that everything is under control?你是否认为一切都在控制之中?
6.undergroundEarthquakes take place far underground .地震则发生在地球的极深处。