Basketball, how to judge which side fouls on the issue of inside confrontation!

Defenders can only touch the attacker with the front, and foul on the side or back.

On the question of internal knocking:

If the attacker violates the rules, such as sinking shoulders and swinging elbows, he will be granted the right to defend the square ball.

If the defender stops and knocks down with strength, it is an offensive foul. If the defender falls to the ground, it is a block foul ~