Ronald seems to know all kinds of serve techniques-the backhand topspin and backspin serves,the forehand topspin and backspin serves,and the high toss serves.
英
美
- 所有的发球技巧,罗纳德似乎都懂-----反手上旋球和下旋球、正手上旋球和下旋球以及高抛球。