There are lots of ways in using "douzu" in a sentence for it is an ambiguous word or a word having several meanings or interpretations.
These are some examples of a sentence in Japanese language with the word "duozu":
Douzu
=> please welcome
ex: irashaimase duozu
=> here you go
ex: denwa wo totte kudasai ( pass me the phone please)
Hai duozu. (here you go)
=> go ahead
ex: nomu ee desuka? (can i drink?)
duozu (go ahead)
=> nice to meet you
ex: i am yuriko nice to meet you.
(watashi wa Yuriko desu. duozu yurushiku)
=> no problem
ex: (swate ee desuka?) can i sit here?
no problem (ee douzu)
Sorry i could only give few.. hope this helps though! :))
--Anika