How Do You Dive Underwater On Pokemon Platinum Nintendo Ds?

There is a tutor that teach it for shards left of pastoria city in a house with a girl with an umbrella

Ok thanks Janedoe74 I thought you could lol...it would be fun...SIGH...
(feeling down)

I know, I wanted to do the same thing..... I have the move dive and I was searching for a place to do it - I guess you can't.... Oh well...