about a period of time which is continuing; for unfinished actions and events; time stated is not finished (with since, for, still, yet) I've practised my piano since 4 o'clock.(it's 4:15) I've lived there for 4 years.(still living there) I stillhaven't finished my homework. Mum hasn't prepared dinner yet. The builder have started working on the kitchen this week.
express recent event (often with just); to focus on the results of an activity or event which is complete Jack hasjustbeen to the bank. I've mentioned the car.(= I've just finished so we can go out in it now)
unspecified past even or time is irrelevant; talk about how many times something has happened (with adverbs like already, before, ever and never; after a superlative) I've lost my new camera.(it's irrelevant when) Pete has been to New York 3 times. I've met her before somewhere. It's the biggest dog I've seen.
happen regularly & habits Jason takes the bus to work every day.
general truth The moon goes round the earth.
permanent situations I work in Central.
to describe the plots of books and films The story begins and ends in Spain. The year is 1937.
for scheduled events with a future meaning timetables - My plane arrives Hong Kong on Saturday at 14:30. programmes - The meeting starts on Wednesday at 9:30. plans - The speaker arrives on Tuesday afternoon.