a)They have seen the tower "Baiterek".
b)They saw the concert last week.
c)They love Rock and Roll. I have liked it all my life.
d)They bought a lot of interesting books after the concert.
e)They have stayed in Astana since October.
f)They have known each other for 5 years.
g)When did they go to Astana?
h)Dmitry went to Astsns 3 months ago.
i)Omar lived / has lived there for 5 months. Вроде бы так )