sentences:  Long-range plans call for widening I-81 to six lanes and effecting further interchange improvements along what is a major commuting and trucking corridor.I-81 crosses the Potomac River from West Virginia and enters Maryland as a four-lane freeway with a speed limit of .The Interstate curves to the northeast around Williamsport, where the highway meets MD 68 and MD 63 (Lappans Road) at a diamond interchange (Exit 1) to the south of the town and US 11 (Virginia Avenue) at a five-ramp partial cloverleaf interchange (Exit 2) to the east.