Hi, maxiewawa.
이미 can roughly translates to 'already' in english as it bears the sense of regret for what's happened at/before the time of speaking.
For example, take 버스는 이미 떠났다 (the bus has already left). In here, 이미 serves as to express one's regret for missing the bus.
On the other hand, 아직 is used when what's been anticipated to happen is not taking place. You could say that 아직 means 'yet' or 'still' in contrast to 'already' for 이미. Suppose if anyone was to say 버스 아직 안 왔어? (isn't the bus here yet?), then you can deduce that the speaker was anticipating the bus to have arrived already.
아직도 means pretty much the same as 아직, but probably implies a stronger sense of disappointment.
Taking the same example at the bus stop, if the bus was still not there 5 minutes after one's said 버스 아직 안 왔어?, then one might let it out in annoyance saying 버스 아직도 안 왔어? (isn't the bus still not here yet????
)
Hope the illustrations helped.
Please help!
