Qiángxíng biàndào shì shìgù de zhǔyào yuányīn zhī yī.
Forced lane changes are one of the main causes of accidents.
Tips
usage
强行 ("by force / without consent") intensifies a verb — here it describes cutting into another lane without signaling or yielding. Under 道路交通安全法, causes 1 point deduction plus fine, and blame shifts entirely to the cutter in any collision.