The present perfect shows the event or the consequence of the event are still going on.
1/ Oh, I'm so sorry, I ----- (break) your vase!
2/ He ----- (learn) Chinese for three years.
3/ ----- (you/always/work) in this company?
4/ How long ----- (you/wait)?
5/ They ----- (not smoke) for 20 days.
6/ We ----- (stay) here since we arrived.
7/ I ----- (never/eat) lobster.
8/ We ----- (not/finish) our lunch yet.
9/ ----- (you/see) my sister?
10/ I ----- (know) him for many years.