Grammar 文法 Man4 faat3̌̌
 

* Different ways of indicating floors
Cantonese
Chinese
British
American
dei6 haa2
地面
Ground floor
Level one
ji6 lau2
二樓
First floor
Level two
saam1 lau2
三樓
Second floor
Level three
sei3 lau2
四樓
Third floor
Level four

Notes:

We call second floor when the British say the first floor.（+/- one floor）　
What shall we call the fourth floor in Cantonese?
There is Chinese taboo on number four 四 “sei3” because its sound is similar to 死 “sei2” (death).
That is why we find some buildings without level four.