Complex sentence: The Tiller Girls were popular dance troupes, first formed by John Tiller in Manchester, England, in 1890, who on visits to the theatre had noticed the overall effect of a chorus of dancers was often spoiled by lack of discipline.
Split into simpler sentences: The Tiller Girls were popular dance troupes, first formed by John Tiller in Manchester, England, in 1890. Whilst on visits to the theatre, Tiller had noticed the overall effect of a chorus of dancers was often spoiled by lack of discipline.