Complex sentence: The 48 contiguous states and federal district are in central North America between Canada and Mexico, with the state of Alaska in the northwestern part of North America and the state of Hawaii comprising an archipelago in the mid-Pacific.
Split into simpler sentences: The 48 contiguous states and Washington, D.C. are in central North America between Canada and Mexico. The state of Alaska is in the northwestern part of North America and the state of Hawaii is an archipelago in the mid-Pacific.