Rules of the Road
Right-of-way rules
At an intersection with no signs or signals, yield to the vehicle on your right. A driver turning left must yield to oncoming traffic going straight or turning right. In a rotary, vehicles already circulating have the right of way, so you yield to your left as you enter and never stop inside the circle to wave someone in. Pedestrians in a marked crosswalk - and in an unmarked crosswalk at an intersection - have the right of way; you must stop for them, not merely slow down.
Speed limits
Massachusetts sets default limits where nothing is posted: 30 mph in a thickly settled or business district, 40 mph on a highway outside such a district, and 50 mph on a divided highway outside such a district. School zones are posted at 20 mph. These defaults are the most common trap on the written test, which often describes a road with no sign and expects the statutory number.
Turns, passing, and emergency vehicles
Unless a sign forbids it, you may turn right on red after a full stop and yielding. Massachusetts also permits a left turn on red from a one-way street onto another one-way street. You may pass on the right when the vehicle ahead is turning left and there is room to do it safely; never pass on a hill or curve with limited sight distance. Under the Move Over Law, shift over a lane and slow down for stopped emergency, tow, and highway-maintenance vehicles with lights flashing.
Worked example: A question says you are on an unmarked road in a thickly settled area. The fastest you may legally drive is 30 mph - not 25 and not 35. If the same road were outside a thickly settled district, the answer would be 40 mph.