In America, it's the first floor.

在美国，这一层则被称为一楼。

youdao

I live on the first floor.

我住在一楼。

youdao

The library is on the first floor.

图书馆在一楼。

youdao

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

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

我住在二层，他住在一层。

普林斯顿公开课 - 人性课程节选

The police video showed officers entering the property and views of the first floor flat.

BBC: Three men in court over Brighton flat squatting

They were standing just inside the hospital, on the first floor by the elevators.

NEWYORKER: I.D.

Working out of the first floor of a beachfront house Robert owns in Manhattan Beach, Calif.

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