When I went to Spain this past Summer, I took the bus from Providence to the Logan Airport in Boston. The bus driver spoke perfect English except when he got the the word Airport. When he said "AEROPÔRTO," I knew where he was from. This happens to me too on certain words. It does not matter how long you have known English, if you came here after a certain age, some words will never be accent free.
Pete Pan Bus, Providence, RI to Boston, MA. August 11, 2012.