mix sb/sth up phr v [T] 1 to think that one person or thing is someone or something else 混淆〔人或物〕: I'm always mixing up the kids' names. 我老是把孩子们的名字弄混。 2 to change the order in which things have been arranged 弄乱〔某物〕: Whatever you do, try not to mix those papers up. 无论你做什么，尽量别把那些文件搞乱了。