Each of these sentences below is grammatically incorrect. Rewrite each sentence correctly.

1. They are as old as us.
2. Can it be them?
3. He had difficulty with the store’s management.
4. I, who’s older, know better than you.
5. Is there any criticism of Arthur going?
6. Everybody tried their hardest.
7. I do not like these sort of cakes.
8. He said that Venus was a planet.
9. I wish I was a clown.