Or they walk up to you later and ask if you understood that math question that morning and you are like, "uhm.I wasn't here for that," and they are just like "really? I didn't even realize that you were gone." ^^So sad but so true
I hate it when that happens i will be in a really good dream then i wake up and i try to go back to sleep but it dosent work. But when i have a bad dream i wake up and then fall back asleep and the bad dream is still there.