sentences:  In 1881, Nielsen began to take his violin playing more seriously, studying privately under Carl Larsen, the sexton at Odense Cathedral.It is not known how much Nielsen composed during this period, but from his autobiography, it can be deduced that he wrote some trios and quartets for brass instruments, and that he had difficulty in coming to terms with the fact that brass instruments were tuned in different keys.Following an introduction to Niels W. Gade, the director of the Royal Academy in Copenhagen, by whom he was well received, Nielsen obtained his release from the military band at short notice, and studied at the Academy from the beginning of 1884.