under the sun 世界上任何地方

　　under the table 台底交易

　　under the weather 身体不适

　　under warranty在保修期内

　　under way (under weight)事情在进展之中

　　up and about 身体复员，可下地走动

　　up to 轮到某人

　　up to one's ears 沉迷；热中

　　up to one's neck 太忙于做某事

　　up to sth 对某事称职

　　use one's name as a reference 让某人推荐

　　very light in weight 很轻

　　very much appreciated  很感激

　　visit John 上厕所