a) I burnt/'ve burnt these burgers a bit. Do you think they're OK? (bo wazny jest rezultat czynnosci)
b) We haven't bought our tickets for the festival already/yet? (bo zdanie przeczace)
c) Kelly works/'s worked here since March. (since sugeruje Perfect)
d) He's had /'s been having this computer for three years. (czynnosc raczej nie jest ciagla, chodzi tylko o posiadanie)
e) They live/'ve lived in the same house since 1967. (mamy since, stad Perfect)