Complex sentence: By 15 December, the British and Spanish withdrew, taking with them 15,000 Royalists, as well as destroying the dockyards and a large number of French warships, although the Royal Navy did lose 10 ships after the French captured the heights overlooking the harbor.
Split into simpler sentences: By 15 December, the British and Spanish withdrew, taking with them 15,000 Royalists, as well as destroying the dockyards and a large number of French warships. The Royal Navy lost 10 ships after the French captured the heights overlooking the harbor.