The tennis serve is a challenging skill to master.
I am not a tennis master I am a normal player
Ah, so you must watch fammous players in their tournaments. Do you have any favorites?
pete sampras my favorite player
How cool! He is, of course retired now after getting his start in 1988, but he truly was a great player--  youngest ever male champion of the US Open at 19 years old! Are you a new fan or long time now?
Did you play tennis as a child or do you play tennis now?
Tennis is very easy to get started with but challenging to be competitive. Its even taught in highschools. Those student are not thought to be able to compete, but rather get some exercise and have some fun. 
Um I learned tennis when I was in high school
Awesome! I imagine it was a gym teacher that taught the classes rather than the schools tennis coach that taught the classes. Im sure you know the source of knowledge is important.