1. They walk along the beach and collect all rubbish.
2. How many tomatoes do you need to make the sauce?
3. My sister does aerobics three times a week to keep fit.
4. Sydney is the most beautiful and the cleanest city in the world.
5. There are eighteen thousand students studying at universary.
Mình làm vậy cũng chả biết đúng ko nữa nên bạn đợi kết quả của ng khác rồi làm nha =))