The purpose of this stroke is to stop your opponent from playing an attacking stroke
forehand, backhand,serves stroke, top spin, slice stroke. yes there are 5.
When the ball hits the tennis racket, topspin (preffered stroke of tennis) makes the ball spin. The upward motion of the racket hitting the tennis ball.
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I am not an expert but still i'm sharing my answers with you. The answer is
Fore hand, back hand, and a serve that scores a point is an ace.