I think one usage might be to create some forward momentum.

来源: Justme 2013-01-29 23:15:27 [] [旧帖] [给我悄悄话] 本文已被阅读: 次 (170 bytes)
Murray steps forward for both 1st and 2nd serves. When the timing is right, it helps to take the ball early and reflect the power of the serving ball back to the server.
请您先登陆,再发跟帖!

发现Adblock插件

如要继续浏览
请支持本站 请务必在本站关闭/移除任何Adblock

关闭Adblock后 请点击

请参考如何关闭Adblock/Adblock plus

安装Adblock plus用户请点击浏览器图标
选择“Disable on www.wenxuecity.com”

安装Adblock用户请点击图标
选择“don't run on pages on this domain”