Помогите с заданием по английскому

Correct the wrong sentences.

1) This is the shop who i was telling you about.
2) I've just been to the new mall, that is much bigger than all the other ones.
3) That's the shop assistant I was telling you about.
4) The Grand Bazaar of Istanbul, that I visited last year, is one of the most exciting places I've been to.
5) The car park, who is supposed to be free for customers, charged us €15.
6) My new computer, which cost me £2000, has broken down!