Hi there, I have recently taken up swimming as a hobby - do you like to swim? 
I love to swim, I like it as a recreation although it can also be a sport, or even survival. I'ts nice for exercise too.
My personal favourite stroke is forward stroke, I find this the best for giving me a complete workout! Which stroke do you like the best? 
I think it's my favorite one too actually. All that matters in swimming is coordinated movements of the whole body and the limbs.
And it's low impact on your joints! I recently damaged my knee running, so I've filled the hole in my exercise plan with swimming! 
Sure! Maybe that's why in some countries swimming lessons are compulsory in the educational system. It's such a useful activity and doesn't damage the body.