Fill in the gaps with relative pronouns: who,which,where,whose. Put brackets round the relative pronoun if it is not

I suppose I’m not a great art lover. I like posters which look good in my bedroom. I usually buy posters (which) I find in big stores. I like buying pictures which go well with my mood. Sometimes, I go to art galleries where I buy copies of famous paintings. I prefer pictures which are realistic. Some people (who) I know spend lots of money on paintings which are really expensive and (which) look horrible. I have a friend whose collection of modern art is very valuable. The paintings (which) he buys are perhaps more sophisticated than mine but I\'m happy with my collection.