It does take a great hunger to be successful at anything.

The good news is I have time.

We lose a lot of young athletes because tennis is such a difficult sport. It's not like kicking a soccer ball.

In America, we love to give people second chances too - as long as you admit you were wrong and come back and do it the right way.

It's really easy to find your friends when you're playing away. You have a close-knit group with you and everyone else is cheering hard for their side. There's more satisfaction coming away with a road victory.

Focusing on one thing can be tough, and people with fewer options are more apt to concentrate on what they're doing. There's probably something to hunger.

Even the poor can be fat in the U.S. That says something about a country. That's how incredible what we have is. But it can also take away incentive.