US biscuit are like a plain scone. They're often served when you have gravy - very nice to sop up meatjuice with. This is why the Yanks are confused when we offer them a biscuit with a cup of tea.

Watercress is a fine green shoot, a bit like a mung bean shoot but finer. You'll see it at the supermarket with the other green stuff

And Grits are basically like porridge, served as a side-dish with things like fried eggs. I've had them once and liked them, but you can see Moxie's reaction.

Each to their own!