Say it ain't so. You've been seated next to a person with atrocious manners. Whether it's a red-eye across the country or a quick connecting flight, you're probably not pleased and have now solemnly vowed to never be that guy or gal. So what are the rudest things you can do on a plane besides the sins the fella beside you in 14C has already committed? Read on for the top five offenses.

1. Resting your feet on the seat in front of you.

There are many times when embracing your inner child is a good thing. Sitting on an airplane with your legs flopped like pool noodles onto the aisle arm rest in front of you or over the seatback is not one of those times.

2. Sporting bare feet.

Not only do we feel sorry for ourselves (the smell, the toes inching closer to our precious invisible legroom boundaries, the podophobia consuming our consciousness), we feel sorry for you. Do you really want to risk stepping on a sharp object and making everybody's flight less enjoyable with a ton of commotion?

3. Reclining without asking permission.

Sure, you could spring your seat backwards with no warning, but would you really want to be on the receiving end of that move? Which, by the way, normally happens at the precise moment said person puts their hallowed airplane bloody mary down on their tray and gets it spilled all over them. For more on the etiquette of seat reclining, read our tutorial here.

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4. Taking a seat that's not yours without getting permission.

Total no-no. Not only for etiquette, but for security reasons, too. For the polite protocol for swapping seats on a plane, click here.

5. Feasting on stinky food and leaving it on your tray even after you're done.

Nothing snaps you out of Beach Mojito Mode like enduring 3.5 hours of super stinky grub on the tray beside you from take-off to touchdown. Don't do it.