Miss Cooper was a teacher works at a school for boys and girls. She taught the chemis

  Miss Cooper was a teacher works at a school for boys and girls. She taught the chemistry for all the students from different grade in the school. Sometimes the new classes learned rapidly, but sometimes they were slowly. One day, one of the classes has been studying for minutes while Miss Cooper suddenly asked, “What is water?” Luckily, nobody could answer the question, so Miss Cooper felt sad. The moment Danny, who was not one of the brightest boys in the class, raised hand, Miss Cooper said in an exciting voice, “Please, Danny!”

“Water is a liquid what has no color until you wash your hands in it, then it turns grey,” replied the boy.

1.works→working 2.the chemistry 去掉the  3.grade→grades 4．slowly→slow

5．has→had  6.while→when  7.Luckily→Unluckily  8.hand前加his

9.exciting→excited  10.what→that/which