Tandem Tai Chi

I had to take a photo of these two men that I spotted on my way to work this morning. I was shy to take a photo of them close up. Thanks to the technology in my camera and on my computer, I can crop and blow up certain parts of photos I take.

What are these two men doing? They were doing Tai Chi like movements in tandem. Perhaps, the older man was teaching or coaching the younger. But they were both very graceful. I should do this with sort of thing with my wife.