Basicly... your entire life.
I personally think there no specific age as long as your good at tennis and you win tournaments you can work your way up.
As the answer would take too long for this website, it is best to refer to the WilsonRacquet.net* link, below, which gives advice on how to become a professional tennis player. * (n.b., WilsonRacquet.net is not affiliated with the Wilson Sporting Goods company)
Ma Long from China
lol, that's funny question. the only answer for that is is "train train train"!
5 to 7 years
For as long as possible if you whant to become really good
Yes. You do need to go to flight School to train how to become a pilot. It depends on how long it takes to be a pilot.
there are several stages you have to go though to become a table tennis official. There are also tests that come with this so its a long process.
The course lasts for one year .
About 2 to 3 years.
For a few years.
9 yrs my dads one
Train and train! If you want to be a long distance runner you have to have a lot of stamina, strengh and speed.
Ma Long from China is #1
How long it takes to become a correction officer depends upon where you are at. Some places will hire you on the spot and train you.
A pro will train for hours a day while not in a tournament. Consisting of not just playing but also weights, cardio, and practing good nutrition. However during a tournament they may practice an hour or less so they will not tire out during their match.
1+ to 2 years of colledge
you can play tennis any were as long as their is a tennis court to play on.
Jimmy Carter is a life long tennis player and to keep in shape he jogs and rides his bike.
Tennis balls are not generally yellow. They are usually green. A tennis ball can become yellow if it is left out in the sun for a very long time (months and months), and will turn yellow due to sun exposure.
A tennis court is 26yds long
You probably mean "Lawn" tennis. Lawn tennis is simply tennis played on a grass court.