Complex sentence: Proceeding south, the Turnpike traverses rugged terrain and features several sharp curves and grades greater than 6%, with a speed limit of 60 MPH which is vigorously enforced by a toll-paid force of state police.
Split into simpler sentences: Proceeding south, the Turnpike traverses rugged terrain and features several sharp curves and grades greater than 6%. The speed limit of 60 MPH is vigorously enforced by a toll-paid force of state police.