4.
1) there
2) there, yes
3) are, are
4) there, aren't
5) is, no
6) there, isn't

6.
1) yes, there is
2) yes, there is
3) my bedroom is big
4) no, there are no cupboards in my bedroom
5) our kitchen is big
6) our house is a new house

7.
big fridge
four chairs and a big table
there is a sofa
there is a computer and a bed
а TV in my bedroom