Complex sentence: In a leg reap, the attacker uses on of his legs to reap one or both of his opponent's legs off the ground, and by controlling the opponent's body with his hands, causes him to fall over.
Split into simpler sentences: In a leg reap, the attacker uses on of his legs to reap one or both of his opponent's legs off the ground. This coupled with the attacker controlling the opponent's body with his hands causes the opponent to fall over.