Rule 166
DO NOT overtake if there is any doubt, or where you cannot see far enough ahead to be sure it is safe. For example, when you are approaching a corner or bend a hump bridge the brow of a hill.
SteerTogether · Official English reference
Read rule 166
Using the road: rules 159–203
Work through moving off, overtaking, junctions, roundabouts, crossings and reversing safely.
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