In British English, we use the present perfect with just, already and yet to talk about recent events and actions.
We use just in positive sentences to talk about very recent events or actions.
- She's just won the match.
- They've just made a big announcement.
We use yet in questions and negative sentences to talk about actions and events happening up to now.
- Have you finished that book yet?
- I haven't made a decision yet.
We use already in positive sentences to talk about actions and events that happened before now or earlier than expected.
- I've already visited three universities.
- Spring has already arrived in Madrid!