Shamsiyan, this is a question that you can easily answer yourself if you look it up. Have you looked up accomodation? If not, according to Longman it's "a place for someone to stay, live, or work" (accommodation - Definition from Longman English Dictionary Online). So you see, an accomodation can serve many purposes. "Office" tells us what kind of accomodation it is. What do people do in an office? They work there.