9. No cutsies
Have you ever waited in a line for what seemed like hours and witnessed someone cut in front of you right before things start to move? It's enough to make you want to scream!
While you may be tempted to throw a fit like Sheldon did in "The Line Substitution Solution" (Episode 23, Season 9), everyone around you will be happier if you act in a calm, adult manner.
Oh, and this should go without saying, but don't let that person be you!
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