There are several ways of saying this in English "These houses are my uncle's" "These are my uncle's houses" "These houses are the ones belonging to my uncle." "These are the houses belonging to my uncle." The focus of the sentence can be varied in spoken English by altering the stress of certain words, something which cannot be represented in writen English. e.g. "These are my uncle's houses" vs "THESE are my uncle's houses" - The latter implies a prior reference to the said houses.