Helppppppp me Please

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1. John is the best singer in his group.
2. Ben is the shortest student in my school.
3. It is the most beautiful building I have ever seen.
4. The Great Wall is the longest structure on the earth.
5. Our house is the oldest house in the street.
6. Sam cooks the best in the group.
7. Bill is the oldest person in his family.
8. This is the least expensive car.
9. Tom is the quickest runner in the school.
10. Alaska is the biggest state in the USA.