4. Do not anticipate other drivers will open a gap for you to enter
When changing lanes on a freeway, signal your intentions and do not anticipate other drivers will open a gap for you to enter.
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Always give signal when you're changing direction. Signal even when you don't see any cars around. It ensures that vehicle in blind spot don't hit you.
Do not anticipate that other drivers will open a space for you to enter. Do not assume that the gap you wish to occupy is clear.