Complex sentence: The first opera commissioned by the group, Brian Easdale's "The Sleeping Children", was premièred in 1951 and, aside from other new works by Britten, the group commissioned and produced eleven other new operas by British composers.
Split into simpler sentences: The first opera commissioned by the group, Brian Easdale's "The Sleeping Children", was premièred in 1951. Aside from other new works by Britten, the group commissioned and produced eleven other new operas by British composers.