它们的意思分别如下:1、check in(在旅馆)登记入住；挂号；（在机场）验票（或护照等）；记录，登记签到例句:I'll ring the hotel. I'll tell them we'll check in tomorrow.(旅馆入住)What time do I have to check in?(飞机检票)2、check out (办理退房手续)结账离开；检查，核实；符合要求例句:I was disappointed to miss Bryan, who had just checked out.(结账退房)She was in San Diego the weekend Jensen got killed. It checked out.(相符一致)。