two groups: people who do x and people who do y.
Barbara was here last night and she put ice in glasses for our drinks. When I went to get ice this morning, I saw that the ice cube tray looked something like this:
When I use ice, I ALWAYS refill the ice cube tray all the way before putting it back in the freezer, but I know (from Barbara) and also from other peoples houses that they don't do that -- they use all the ice before refilling.
The world is divided into two kinds of people: those who refill the ice cube tray immediately and those who use all cubes before refilling.
Which are you?