You must yield the right-of-way to an approaching vehicle when you are:

When drivers approach the same intersection from opposite directions at about the same time, drivers turning left must yield to traffic that is going straight or turning right. If a driver traveling straight approaches an intersection where another driver is already making a left turn, they must let that vehicle complete its turn before entering the intersection. Drivers entering a traffic circle or rotary must yield to drivers already in the circle.
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