例句：I hate going to weddings! Mom always makes me dress up in some uncomfortable suit and tie. And the leather shoes too make my feet ache for hours afterwards.

　　那男孩讨厌去参加婚礼，原因是他妈妈老是要他穿上令人不舒服的西服、戴上领带，还有那皮鞋还会让他过后脚疼好半天。

　　显然在这儿dress up是指认真打扮起来。换句话说，是穿上讲究的正式服装，打扮得体面出众。