Complex sentence: She attended George Heriot's School where, at the age of 14, she started rowing on the Union Canal, and went on to study medicine at the University of Edinburgh until taking a sabatical to concentrate on rowing.
Split into simpler sentences: She attended George Heriot's School where, at the age of 14, she started rowing on the Union Canal. She went on to study medicine at the University of Edinburgh until taking a sabbatical to concentrate on rowing.