Complex sentence: The Halfan industry is one of the Late Epipalaeolithic industries of the Nile Valley that begin to appear by 22,000 BP and is one of the earliest known backed-bladelet industries in Eastern Africa and is dated to between 19,000 and 14,000 BP in Nubia and Egypt.
Split into simpler sentences: The Halfan industry is one of the Late Epipalaeolithic industries of the Nile Valley that began to appear by 22,000 BP. It is one of the earliest known backed-bladelet industries in Eastern Africa, largely dating between 19,000 and 14,000 BP in Nubia and Egypt.