Knowledge: Tennis is a competitive sport and the prize money for male and female are the same unlike other sports. On the other hand,  underwater football a playing football below the water.

Conversation:
Hello, I a newbie when it comes to water sports but I enjoy kayaking in my free time.
Well, there are dozens of commonly played sports that involve water.
I like to be on top of water not in it
I understand, so you probably don't like the sports that take place under or in water.
I am not a very good swimmer so I only like it if I am able to float on something.
How do you feel about underwater football?
Eh, what kind of sport is that?

Response: Yeah, underwater football a playing football below the water.