What is the difference between, sleepy, tired, and fatigue? Or are the the same?
It's fatigued, since you mentioned the past tense tired, the past tense of fatigue is fatigued and is usually brought on by some kind of exertion. I would say sleepy, tired, and fatigued are all synonyms.
Not really, fatigue means your light headed and sleep probably won't get rid of the problem like it would for being tired. It helps but usually feeling fatigue or light headed means your body is lacking some key substance that sleep can't replace.
Tired is more of an adjective, where you can use it for both present and past tense. i.e: I am tired, I was tired. On the other hand, fatigue is a noun. If you're going to use it as an adjective, you have to add the 'd' at the end. i.e: I am fatigued. Sleepy would be more of a casual tired.
