1. How often does Julia play the piano? 2. What do Helen and his sister do when it's hot? 3. Our family is going to stay in Nha Trang beach for 5 days. 4. Why don't you do your homework before going out? 5. They are playing soccer with their friends in the park now. 6. There are too many vehicles in Ha Noi and too much noise. 7. Minh and his classmates are playing volleyball now. 8. We usually go walking in the mountains on the weekend. 9. How many times does your sister go camping in a year? 10. I always do my homework in the evening. 11. In the future, home robots will be able to do all our housework. 12. I couldn't speak until I was three years old. 13. Will robots be able to talk to us in 2030? 14. If the water is polluted, fish will die badly. 15. If you walk to school, it will help reduce the air pollution.