Final answer:
It is true that drivers should yield to cars already in a traffic circle to ensure right of way and maintain a smooth traffic flow.
Step-by-step explanation:
The question you're asking pertains to proper traffic procedures and safety practices when driving. To answer your question directly, it is true that when you are driving into a traffic circle, also known as a roundabout, you should yield to cars already in the circle. Vehicles inside the circle generally have the right of way, and those entering must wait for a safe opportunity to join the flow of traffic.
This rule helps to maintain a smooth traffic flow and prevent collisions within the circle. In roundabouts, traffic continuously moves in one direction around a central island, and yielding upon entry reduces potential conflict points between vehicles. Always remember to obey traffic signs and signals, and pay attention to other drivers and pedestrians to ensure everyone's safety on the road.