8:

2.These are Tony'pencils and Bill's pencil.

   They're their pencils.

   These pencils are theirs.

3.This is Mum'apron.

   It's her apron.

   This apron is hers.

4.This is The roof .

   It's house'roof.

6:

1.friend's

2.cat's

3.children's

4.Philip's and Lucy's

5.the leaves of the tree

6.her

7.gilr's

8.cousin's

7:

2.wife/a/Frank's

3.a child/a/Alan's

4.a/Katie's

5.wife/husband/

5:

1.C

2.C

3.A

4.B

5.C

6.B

5.

2.C

3.A

4.B

5.C

6.B

6.

2. cat's

3. children's

4. Philip's and Lucy's

5. the leaves of the tree

6. her

7. girls

8. cousin's