What should be done before changing lanes?

Before changing lanes, it is essential to signal and check mirrors. Signaling indicates your intention to other drivers, helping to ensure safety on the road. Using turn signals allows surrounding vehicles to anticipate your movement, reducing the risk of accidents. Checking mirrors is vital to gain awareness of the traffic around you, including any vehicles that may be in your blind spots. This comprehensive approach helps you make an informed decision about when it is safe to change lanes.

The other options, such as doing a U-turn or accelerating quickly, are inappropriate actions when changing lanes and can lead to dangerous situations. Only looking to the left neglects the need to check for vehicles approaching from multiple directions, particularly those that may be in the right-side blind spot. Therefore, signaling and visually confirming the lane is clear is the safest and most responsible procedure before making a lane change.