Complex sentence: From 1984 to 1991, he was principal conductor of the Hallé Orchestra, and in 1988, was composer-in-residence for the Philadelphia Orchestra's summer season at Saratoga.
Split into simpler sentences: From 1984 to 1991 he was principal conductor of the Hallé Orchestra. In 1988, he was composer-in-residence for the Philadelphia Orchestra's summer season at Saratoga.