This is the 870th most frequent Polish word.
dwa
The Polish word "dwa" means "two" in English.
The word 'dwa' is used here as a numeral indicating the quantity of the noun 'cats'.
Mam dwa koty.
I have two cats.
The word 'dwa' is functioning as part of the adverbial phrase to specify the number 'two' in repeating the action.
Dwa razy to zrobiłem.
I did it two times.
Here, 'dwa' is used to describe the exact number of the noun 'chairs' being referred to in the question.