Complex sentence: He is said to have spent so much time in hunting, fishing, and the delights of the countryside, that he neglected painting, though his biography shows him to be exceedingly prolific in altarpieces.
Split into simpler sentences: He is said to have spent so much time in hunting, fishing, and the delights of the countryside, that he neglected painting. Though his biography shows him to be exceedingly prolific in altarpieces.