These adverbs give additional information about when something happens.

Ago

Ago simply means in the past. For example:
- I graduated university 3 years ago.
- We moved to Canada just 2 months ago.

Already

Already is used when something happens before it is expected. For example:
- He's only 13, but he already speaks three languages.
- Can you finish this by tomorrow? Sure, it's already finished.
- You don't need to feed the dog, I've already done it.

Anymore

Anymore is used when something has has changed from what we expect. For example:
- I want to email her, but her address isn't working anymore. (It worked before, but not now)
- My friend used to live here, but she doesn't live here anymore.
- I don't want to work here anymore. (I wanted to work here, but no I don't like working here.)

Just

Just is used for something that happened very recently. For example:
- I just found out my test score, I got an A!
- What was that noise? - Sorry, I just broke a glass.

You can also use jJust about for something that will happen very soon.
- Are you finished? - Yes, I'm just about to go home.
- I'm hungry. - If you wait 5 minutes, I'm just about to make some lunch.

Still

Still is used when something happens for longer than expected. For example:
- Did you get a new job? No, I'm still working at my old one.
- She's 65 years old, but she still exercises 3 times a week.

Still is also used to confirm that an activity or situation is continuing and that nothing has changed. For example:
- Are you still studying English? Yep, I still study a little every day.
- Do you still want to go abroad? Of course, I'd love to!

Yet

Yet is used when something hasn't happened that is expected. It is used negative sentences and questions. For example:
- Are you finished? No, I'm not finished yet.
- Has the mail come yet? No, it's not here yet.

Still can be used with a similar meaning. For example:
- My parents haven't arrived yet.
- My parents still haven't arrived.
Still in negative sentences and questions often shows impatience or that something is unexpected.
Note that yet is usually at the end of the sentence, wheras still comes before the negative form.

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