9. First pre filter the cloudy water with a cotton filter or folded cloth. Then boil the filtered water. Add a small amount of salt 10. Anna review hard for the exam, she got a high score. 11. On that night, I opened my bedroom window wide so I could watch the twinkling of the stars. 12. Kyle fails to wake up early for the field trip. Mother calls up the school to inform the teacher. 13. The doors of the aircraft closed automatically and some passengers got locked inside 14. The school campus becomes dirty during lunch, recess and dismissal. The pupil government launches anti-littering campaign. 15. The astronaut successfully landed in the moon. So they spent a day on​