Going straight ahead. If you are going straight ahead at a junction, you have priority over traffic waiting to turn into or out of the side road, unless road signs or markings indicate otherwise (see Rule H3). Check that you can proceed safely, particularly when approaching junctions on the left alongside stationary or slow-moving traffic. Watch out for drivers intending to turn across your path. Remember the driver ahead may not be able to see you, so bear in mind your speed and position in the road.
Take great care when deciding whether it is safe to pass stationary or slow-moving lorries and other long vehicles, especially at the approach to junctions, as their drivers may not be able to see you. Remember that they may have to move over to the right before turning left, and that their rear wheels may then come very close to the kerb while turning (see Rule 67).
Advice, not law. This rule is not written in capitals, so breaking it is not an offence in itself — but it can still be used in evidence in court to establish liability. The rules that say MUST or MUST NOT are the ones backed by law.
5 theory test questions on this rule
From the DVSA revision question bank. These are not the questions asked in the real theory test. Each one shows the answer, the explanation, and our own note on why every other option is not it.