When exiting a roundabout, vehicles must use the right turn signal. Below is a detailed analysis of specific scenarios: Turning left at a roundabout: If a vehicle intends to turn left, it should choose the left lane inside the roundabout. Since the vehicle needs to merge from the outer lane to the inner lane, it should activate the left turn signal upon entering the roundabout to signal to other vehicles inside and behind it: 'I am merging into the inner lane to turn left, please be aware.' Before exiting the roundabout, the vehicle should activate the right turn signal in advance, ensure safety, and then begin changing lanes from the inner lane to the outer lane before finally exiting the roundabout. Going straight at a roundabout: If a vehicle intends to go straight, it should choose the middle lane inside the roundabout. Since the vehicle does not need to change lanes after entering the roundabout, it does not need to activate the left turn signal when entering. When preparing to exit the roundabout to continue straight, the vehicle must cross the right lane inside the roundabout, so it should activate the right turn signal to alert other vehicles before exiting. Turning right at a roundabout: If a vehicle intends to turn right toward another intersection, it can choose the right lane inside the roundabout or turn right from the outer lane. The situation when entering the roundabout is similar to going straight, so the left turn signal is not required. After selecting the corresponding exit, the vehicle should activate the right turn signal in advance, ensure safety, and then turn right to exit the roundabout. From the analysis of these three scenarios, it is clear that vehicles only need to use the left turn signal when entering the roundabout in one case—when turning left. In the other two cases, the left turn signal is not required. However, vehicles must always use the right turn signal when exiting the roundabout.
