（楼下有朋友要谈谈网球，俺在这方面稍有体会，算抛砖引玉吧）
现在喜欢网球的人不少，大部分的朋友虽然打了很久的球，但很少有人真正知道自己到底是一个什么样的水准。
网球不仅是娱乐，也是一项技巧性非常非常高的竞技项目。大部分爱好者只停留在底线抽杀的练习阶段，而很少打Game。要知道即使你能在正手和反手和你的球伴在练习是抽１０个来回Top spin，并不意味着你在Game里能保持一贯的Consistency。网球的规则，场地和球的速度决定的它是力量和技巧性的高度统一。力量意味着主动，而技巧则是对场地的充分利用。如果大家有机会看阿加西打球，就会发现他对场地的利用以到了出神入化的地步。这就是年过３０力量并不在优势的阿加西能高居ATP排名第一的原因。
网球的主要技术有正反手上旋抽杀（top spin),削球（Slice)，截击（volley)，接发球，高空球等。针对不同的技术，握拍（Grip)的方法也不同。比如top spin用东方式为好，而发球和截击可采用大陆式。对于初学者，第一步要掌握的就是正确的握拍。握拍也是很多网球爱好者容易疏忽的地方。很多人说为什么我就打不出漂亮的上旋呢，现检查一下你的握拍吧。
既然网球是一项竞技，网球水平的提高还得靠实战。实战和练习完全不同。举个例子：如果你在练习中第一发球的命中率有５０％，在实战中你会全部miss掉。而且只有在实战中才能找到各种不同球的落点的感觉，从而迅速提高你的consistancy。在网球中，Consistancy是衡量水平高低的重要指标。
说了这么多，现在规入正题。围棋有段位，柔道有分级，对于网球水平的评估也有标准。US tennis association leagues有一个NTRP(national tennis rating program)。这是一个美国的国家标准，主要适用于从业余学者，中级水平，高校水平甚至能判断是否具有职业水准。
规则分为七级，以阿拉伯数字标识。每级之间另有半级作为过渡用。如果你第一次拿起网球拍，踏进球场你就是１.0。如果你做空中飞人靠参加国际大赛挣奖金为生，那么你是世界级的选手，你的NTRP的级别是最高级７.0。当然这个7.0对你已没有任何意义，你得靠世界排名来证明自己。可以这么说，NTRP对业余者意义更大。对照它，你可以知道该向那方面努力才能到更高的水平。
１.0 到２.5: 初学者，习惯于正手击球，不喜欢反手；不能适当地上网截击。没有consistency，抛球（toss)没有consistancy，基本不会接发球。
３.0 到3.5：这时大部分有一定球龄爱好者集中的水平段。已能够自由使用正反手，能控制方向，有上网截击的意识，对中等力量的球有良好的consistancy。 发球以开始控制落点和力量，能接住中等力量的发球。
4.0到５.0：开始进入业余高手的行列。好比围棋的业余一，二段（不恰当的比喻：）。正反手能有效利用速度和旋转；能很好地控制击球深度。上网截击步伐良好，能控制截击的方向和深度。发球能利用力量和旋转，极少有发球双误。
5.0到５.5: 已经是相当高的业余选手了。力量和consistency已成为武器。能够发现和分析对手的弱点，在竞争中有良好的策略。
６.0到7.0：６.0级别基本上已是college level的水平，通常在地区和全国有排名。7.0指的是职业选手。
大概说了一下US NTRP的标准，朋友们可以对照一下自己在哪一段。如果认真一点的话，不妨请一个网球coach鉴定一下。这一篇抛个砖，希望看到更多关于网球的文章。
附录：
Complete NTRP Scale
NATIONAL TENNIS RATING PROGRAM
Verification Guidelines
1.0
This player is just starting to play tennis
1.5
This player has limited experience and is still working primarily on getting the ball into play
2.0
FOREHAND: Incomplete swing; lacks directional intent
BACKHAND: Avoids backhands; erratic contact; grip problems; incomplete swing
SERVE/RETURN OF SERVE: Incomplete service motion; double faults common; toss is inconsistent; return of serve erratic
VOLLEY: Reluctant to play net; avoids BH; lacks footwork
PLAYING STYLE: Familiar with basic positions for singles and doubles play; frequently out of position
2.5
FOREHAND: Form developing; prepared for moderately paced shots
BACKHAND: Grip and preparation problems; often chooses to hit FH instead of BH
SERVE/RETURN OF SERVE: Attempting a full swing; can get the ball in play at slow pace; inconsistent toss; can return slow paced serve
VOLLEY: Uncomfortable at net especially on the BH side; frequently uses FH racket face on BH volleys
SPECIAL SHOTS: Can lob intentionally but with little control; can make contact on overheads
PLAYING STYLE: Can sustain a short rally of slow pace; weak court coverage; usually remains in the initial doubles position
3.0
FOREHAND: Fairly consistent with some directional intent; lacks depth control
BACKHAND: Frequently prepared; starting to hit with fair consistency on moderate shots
SERVE/RETURN OF SERVE: Developing rhythm; little consistency when trying for power; second serve is often considerably slower than first serve; can return serve with fair consistency
VOLLEY: Consistent FH volley; inconsistent BH volley, has trouble with low and wide shots
SPECIAL SHOTS: Can lob consistently on moderate shots
PLAYING STYLE: Consistent on medium-paced shots; most common doubles formation is still one-up, one-back; approaches net when play dictates but weak in ????ution
3.5
FOREHAND: Good consistency and variety on moderate shots; good directional control; developing spin
BACKHAND: Hitting with directional control on moderate shots; has difficulty on high or hard shots; returns difficult shot defensively
SERVE/RETURN OF SERVE: Starting to serve with control and some power; developing spin; can return serve consistently with directional control on moderate shots
VOLLEY: More aggressive net play; some ability to cover side shots; uses proper footwork; can direct FH volleys; controls BH volley but with little offense; difficulty in putting volleys away
SPECIAL SHOTS: Consistent overhead on shots within reach; developing approach shots, drop shots; and half volleys; can place the return of most second serves
PLAYING STYLE: Consistency on moderate shots with directional control; improved court coverage; starting to look for the opportunity to come to the net; developing teamwork in doubles
4.0
FOREHAND: Dependable; hits with depth and control on moderate shots; may try to hit too good a placement on a difficult shot
BACKHAND: Player can direct the ball with consistency and depth on moderate shots; developing spin
SERVE/RETURN OF SERVE: Places both first and second serves; frequent power on first serve; uses spin; dependable return of serve; can return with depth in singles and mix returns in doubles
VOLLEY: Depth and control on FH volley; can direct BH volleys but usually lacks depth; developing wide and low volleys on both sides of the body
SPECIAL SHOTS: Can put away easy overheads; can poach in doubles; follows aggressive shots to the net; beginning to finish point off; can hit to opponent's weaknesses; able to lob defensively on setups; dependable return of serve
PLAYING STYLE: Dependable ground strokes with directional control and depth demonstrated on moderate shots; not yet playing good percentage tennis; teamwork in doubles is evident; rallies may still be lost due to impatience
4.5
FOREHAND: Very dependable; uses speed and spin effectively; controls depth well; tends to overhit on difficult shots; offensive on moderate shots
BACKHAND: Can control direction and depth but may break down under pressure; can hit power on moderate shots
SERVE/RETURN OF SERVE: Aggressive serving with limited double faults; uses power and spin; developing offense; on second serve frequently hits with good depth and placement; frequently hits aggressive service returns; can take pace off with moderate success in doubles
VOLLEY: Can handle a mixed sequence of volleys; good footwork; has depth and directional control on BH; developing touch; most common error is still overhitting
SPECIAL SHOTS: Approach shots hit with good depth and control; can consistently hit volleys and overheads to end the point; frequently hits aggressive service returns
PLAYING STYLE: More intentional variety in game; is hitting with more pace; covers up weaknesses well; beginning to vary game plan according to opponent; aggressive net play is common in doubles; good anticipation; beginning to handle pace
5.0
FOREHAND: Strong shot with control, depth, and spin; uses FH to set up offensive situations; has developed good touch; consistent on passing shots
BACKHAND: Can use BH as an aggressive shot with good consistency; has good direction and depth on most shots; varies spin
SERVE/RETURN OF SERVE: Serve is placed effectively with the intent of hitting to a weakness or developing an offensive situation; has a variety of serves to rely on; good depth, spin, and placement on most second serves to force weak return or set up next shot; can mix aggressive and off-paced service returns with control, depth, and spin
VOLLEY: Can hit most volleys with depth, pace, and direction; plays difficult volleys with depth; given opportunity, volley is often hit for a winner
SPECIAL SHOTS: Approach shots and passing shots are hit with pace and a high degree of effectiveness; can lob offensively; overhead can be hit from any position; hits mid-court volley with consistency; can mix aggressive and off-paced service returns
PLAYING STYLE: Frequently has an outstanding shot or attribute around which his game is built; can vary game plan according to opponent; this player is 'match wise,' plays percentage tennis, and 'beats himself' less than the 4.5 player; solid teamwork in doubles is evident; game breaks down mentally and physically more often than the 5.5 player
5.5
This player can hit dependable shots in stress situations; has developed good anticipation; can pick up cues from such things as opponent's toss, body position, backswing, preparation; first and second serves can be depended on in stress situations and can be hit offensively at any time; can analyze and exploit opponent's weaknesses; has developed power and /or consistency as a major weapon; can vary strategies and style of play in a competitive situation.
6.0 to 7.0
These players will generally not need NTRP ratings. Rankings or past rankings will speak for themselves. The 6.0 player typically has had intensive training for national tournament competition at the junior level and collegiate levels and has obtained a sectional and/or national ranking. The 6.5 player has a reasonable chance of succeeding at the 7.0 level and has extensive satellite tournament experience. The 7.0 is a world class player who is committed to tournament competition on the international level and whose major source of income is tournament prize winnings.
