My wife and I love to go scuba diving. Have you ever tried it?
No, I'm a little afraid of breathing underwater!
I'm pretty new myself. Do you know much about how to do it! We could use some tips.
Well divers carry their own source of gas, which allows them to more with greater independance. 
Yes! It's a really fun experience. Do you know when people first started scuba diving throughout history?
Not really but it takes a lot of tech to get the high pressure gas into the cylinders and you need a regulator.