I don't know what is the difference between "wach" and "erwacht", specially in this sentence: "Du bist noch nicht ganz erwacht." or "Du bist noch nicht ganz wach." Could anyone please describe me the difference?
There is not much of a difference in the meaning. The verb in infinite itself e.g. on DWDS: switching from the state of sleeping to being awake.
Du bist noch nicht ganz erwacht. vs. Du bist noch nicht ganz wach.
The main difference:
- style of writing
- "erwachen" is a process over a time period
- "wach sein" is a state at a point in time
- which derives the meaning mainly from "sein"
=> "erwacht sein" is also a point in time and might refer to the end of an awakening process while "wach sein" does not talk about the process.
In your example there is no real difference - I guess either one of it was used beforehand so it was used again.
- there is a religious group with their paper called "Erwachet!"
- they claim that you need to go through a process and at the end you understand their version of truth.
Erwacht concentrates on the transition between sleeping and awake, so the sleeping unawareness is still important. It is also used figuratively to describe the establihment of feelings, moods etc.
Wach is simply the state. This is too used figuratively, but then means something like alert, keen, sharp