三层

sān céng de gōng yù dà lóu

三层的公寓大楼

three-story apartment

wǒ men chéng zhe yī bù lǎo jiù diàn tī dào dá le sān céng

我们乘着一部老旧电梯到达了三层。

We took an old elevator up to the third floor.