10. My sister is a fluent French speaker.
11. The red car is more expensive than the black one.
12. No houses are younger than mine.
13. It's very interesting to have a vacation abroad.
14. What is the price of a letter to the USA?
15. We spend half an hour walking to school.
16. Is this the cheapest computer you have?
17. Tim's collection has over eight hundred stamps.
18. How much does this bag cost?
19. What is the weight of your son?
20. You ought not to eat too many candies.
10. My sister speaks French fluently.
=> My sister is a fluent French speaker.
11. The black car is cheaper than the red car.
=> The red car is more expensive than the black car.
12. My house is the oldest house on the streer.
=> No house on the street is older than my house.
13. Having a vacation abroad is very interesting.
=> It's very interesting to have a vacation abroad.
14. How much does it cost to mail a letter to the USA?
=> What is the price of mailing a letter to the USA?
15. It takes us about half an hour to walk to school.
=> We spend about half an hour walking to school.
16. Do you have a cheaper computer than this?
=> Is this the cheapest computer you have?
17. There are over eight hundred stamps in Tim's collection.
=> Tim's collection has over eight hundred stamps.
18. What is the price of this bag?
=> How much is this bag?/ does this bag cost?
19. How heavy is your son?
=> What is the heaviness of your son?
20. You shouldn't eat too much candies.
=> You ought not to eat too much candies.