Caffeine

Sleep is one of the great mysteries of life; 6 to 8 hours sleep per night is more than enough for a adult like us.

It's seems like I never got enough sleep during the night, and will try to remedy during the day, after my class or whenever I'm free.

15 minutes would be enough for a snooze to chase off the tiredness; I always have my alarm off after it rang for the first time, and will just wake up naturally after I had enough sleep, this surely a bad habit, shouldn't waste my time for that.

| Blear-eyed |

Sleep is a symptom of caffeine deprivation.