Here's how people break this rule:
- By completely ignoring you, including not even looking at you. Excuse me! I'm talking to you here. I'm not whispering and I'm like five feet away from you. I know you heard me.
- By looking at you, but not answering. This is awkward because it further confirms that you definitely heard what I said. You're seriously going to make eye contact and everything but not answer my question?
- By answering, but not reciprocating. Oh, so you're doing fine, but you don't care how I'm doing? Thanks, good to know that you don't consider me a person worthy of consideration.