點樣可以將個波打得又快又大力，而唔會出界 ( 指發球線果條界

A powerful forehand or backhand may not mean that you have to use your whole power to play. The most important thing is that you have to play with the correct form and with 'follow through' action. Sometimes you can add some 'top spin' with your wrist so that the ball can drop at the base line. Of couse this should be played only if you are a sophisticated player since this may heart your wrist.

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