Complex sentence: It has been one of the world's most popular hobbies since the late nineteenth century with the rapid growth of the postal service, but is now in decline with the rise of the internet which has sharply reduced the number of postal items arriving in households.
Split into simpler sentences: It has been one of the world's most popular hobbies. Since the late nineteenth century with the rapid growth of the postal service but is now in decline with the rise of the internet which has sharply reduced the number of postal items arriving in households.