汉语中的“一楼、二楼、三楼......”在美国英语中为“the first floor, the second floor, the third floor...”，但在英国英语中却是“the ground floor, the first floor, the second floor...”。即：

I sleep on the third floor. 我睡在三楼。（美国英语）

They took the lift to the fourth floor. 他们坐电梯到了五楼。（英国英语）