using (must,mustn't,have to,don't have)
1.Children go to school.
2.Millionaires work.
3.You to go to England if you want to learn English.
4.In Hong Kong,you drive on the left.
5.You pay bills.
6.You go out with your friends.
7.You tell your Mum and Dad where you are going.
8.Adults worry about paying the bills.
9.We bring mobile phones into class.
10.We do our homework.