A. still
It is still raining now.
still = something is the same as before:
• I had a lot to eat but I'm still hungry. (= I was hungry before and I'm hungry now)
• 'Did you sell your car?' 'No, I've still got it.'
• 'Do you still live in Barcelona?' 'No, I live in Madrid now.'
B. yet
Bill hasn't come yet.
yet = until now:
We use yet in negative sentences (He hasn't come yet.) and in questions (Has he come yet?).
Yet is usually at the end of a sentence:
• A: Where's Diane?
B: She isn't here yet. (= she will be here but until now she hasn't come)
• A: What are you doing this evening?
B: I don't know yet. (= I will know later but I don't know at the moment)
• A: Are you ready to go yet?
B: Not yet. Wait a moment. (= I will be ready but I'm not ready at the moment)
• A: Have you finished with the newspaper yet?
B: No, I'm still reading it.
Compare yet and still:
• She hasn't gone yet. = She's still here. (not 'She is yet here')
• I haven't finished eating yet. = I'm still eating.
C. already = earlier than expected
• 'What time is John arriving?' 'He's already here.' (= earlier than we expected)
• 'I'm going to tell you what happened.' 'That's not necessary. I already know.'
• Ann doesn't want to go to the cinema. She has already seen the film.
still
I'm still hungry.
I've still got it.
I live in Madrid now.
yet
She isn't here yet.
I don't know yet.
Not yet.
already
He's already here.
I already know.
She has already seen the film.