Complex sentence: The AT&T Long Lines microwave relay network provided long-distance transport services to AT&T and its customers from the late 1940s to the early 1980s, as fiber optic communications and satellite networks gradually replaced it.
Split into simpler sentences: The AT&T Long Lines microwave relay network provided long-distance transport services to AT&T and its customers from the late 1940s to the early 1980s. Fiber optic communications and satellite networks gradually replaced it.