Sure, here is the completed conversation:

Mi: The living room looks so old and shabby now.
Mum: I think so, too. How about redecorating it, Mum?
Mi: Great idea.
Mum: What shall we do first, Mum?
Mi: Let’s first clean the floor and dust the furniture.
Mum: Yes, Mum. Then, why don’t we change that old curtain?
Mi: That sounds good. I’ll go and buy a new one.
Mum: How about replacing the paintings on the wall with some family photos, Mum?
Mi: Well, those paintings still look fine. Dad likes them very much.
Mum: I see, Mum. He painted them by himself.
Mi: Why not, Mum? The sofa will look much nicer then.