Complex sentence: The 10-point must system is a method of scoring a fighting match (e.g., boxing or mixed martial arts (MMA)) in which the judges must give the winner of a round 10 points, and the loser 9 points or fewer.
Split into simpler sentences: The 10-point must system is a method of scoring a fighting match (e.g., boxing or mixed martial arts (MMA)). Under the system, the judges must give the winner of a round 10 points, and the loser 9 points or fewer.