1. 上楼；往楼上
If you go upstairs in a building, you go up a staircase towards a higher floor.
e.g. He went upstairs and changed into fresh clothes...
他上楼换上干净衣服。
e.g. I walked upstairs and unlocked my front door.
我走上楼去，打开前门的锁。
2. 在楼上
If something or someone is upstairs in a building, they are on a floor that is higher than the ground floor.
e.g. The restaurant is upstairs and consists of a large, open room...
饭店在楼上，有一个宽敞的开间。
e.g. The boys are curled asleep in the small bedroom upstairs.
男孩们蜷缩在楼上的小卧室里睡熟了。
3. 楼上的
An upstairs room or object is situated on a floor of a building that is higher than the ground floor.
upstairs的近义词
e.g. Marsani moved into the upstairs apartment.
马萨尼搬进了楼上的公寓里。
e.g. ...an upstairs balcony.
楼上的阳台
4. 楼层
The upstairs of a building is the floor or floors that are higher than the ground floor.
e.g. Together we went through the upstairs...
我们一起走过各层楼。
e.g. Frances invited them to occupy the upstairs of her home.
弗朗西丝邀请他们住在她家的楼上。