1. Right-of-way at uncontrolled intersections
When there's no stop sign or signal, the driver who arrives first goes first — if it's a tie, the car on the right has priority.
2. Blood alcohol concentration (BAC) limits
The legal limit and the lower limit for drivers under 21 are easy to mix up, and test-takers often get the numbers backwards.
3. Safe following distance
Most people know "leave space," but miss the specific rule — the 3-to-4-second gap behind the car ahead, especially in rain or fog.
4. Stopping distance for school buses
The required distance (commonly 20 feet) when a bus has its lights flashing and stop sign extended is one of the most frequently missed specifics.
5. Roundabout rules
Yielding to traffic already in the circle, and knowing when to signal, trips people up since it's newer material than older intersection rules.