Complex sentence: Bournemouth started to grow at a faster rate as George William began developing the area like the south coast resorts of Weymouth and Brighton but despite enormous investment, the town's share of the market remained modest.
Split into simpler sentences: Bournemouth started to grow at a faster rate as George William began developing the area like the south coast resorts of Weymouth and Brighton. But despite enormous investment, the town's share of the market remained modest.