There are two words that means "Please" in Cantonese:
- 請 （ 请 ） (this may also mean ask or invite)
- 唔该 (this phrase can also mean "Thank you". Literately it means "not deserved" or "should not (bother you). " )
We can use them interchangeably. The first form is more formal.
1. Please open your books: 請打開你嘅書。cing2 daa2 hoi1 nei5 ge3 syu1
2. Please say that again （once more ）: 唔该你讲多一次。 m4 goi1 nei5 gong2 do1 jat1 ci3
or we can also say 請你讲多一次。cing2nei5 gong2 do1 jat1 ci3
3. Could you say that again, please?: 唔该你可唔可以讲多一次? m4 goi1 nei5 ho2 m4 ho2 ji5 gong2 do1 jat1 ci3
or we can say: 可唔可以請你讲多一次? ho2 m4 ho2 ji5 cing2nei5gong2 do1 jat1 ci3
可以 = can ; could
可唔可以 = could or could not; can or cannot
Other Usage of 請
- 邀請 verb. invite ; noun. invitation.
e.g. May I ask/invite you to come to my home?
我可唔可以邀請你來我屋企。ngo5 ho2 m4 ho2 ji5 jiu1 cing2 nei5 loi4 ngo5 nguk1 kei5
- 請假 ask for leave
e.g. 我想請（病）假 I want to ask for (sick) leave. ngo5 soeng2 cing2 beng6 gaa3
病 = sick
- 請問 Could you please tell (me/us) ..?
e.g. Could you tell me where is the toilet? 請問廁所喺邊度? cing2 man6 ci3 so2 hai2 bin1 dou6
... 喺邊度? = where is ... ?