3.My friend's fish

4.my parents' flat

6.my friend's son

7.my friends' son

8.my friends' sons

9.the farmer's sheep

10.farmer's sheep

11.farmers' sheep

12.new baby's teeth

13.my sister's bookcase

14.my parents' bookcases

15.my friends' songs

16.my parents' bower

17.kids' voices in the street

18.Charles Darwin's books

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