I live on the second floor, and he lives on the first floor.

我住在二层，他住在一层。

youdao

Our Western restaurant on the First floor.

我们的西餐厅在三层。

youdao

Menswear is on the first floor.

男装在第二层。

《牛津词典》

Cows were kept on the first floor and the one above was used to store hay.

VOA: special.2009.12.29

I know some of you come from Europe and other parts of the world where the ground floor is rez-de-chauss?e or some silly thing like this 1 and you push a button on the elevator to one and you go up to the first floor.

我知道你们中间有些人来自欧洲,或者世界其他地方，你们那里的一楼,和地面齐平，或者像这样可笑的事情,比如你要按下电梯的按钮,然后才能上到真正的1楼。

麻省理工公开课 - 固态化学导论课程节选

First, take the case in the elevator is on the ground floor of some building and completely addressed.

首先我们来看看电梯,在一楼时候的情况

耶鲁公开课 - 基础物理课程节选

I'd hear him get off the couch and walk to the only phone on our first floor, the one hanging on the wall in the kitchen with the 50-foot-long, tangled cord.

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On the first floor of the hospital, in the lobby to the left on a stretcher, I saw a body wrapped in a sheet.

CNN: STORY HIGHLIGHTS

The Parts Dept. was on the first floor and one of my jobs was to take cans of oil on a trolley down to the petrol station below for sale to motorists buying petrol.

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