надо написать 8 предложений правил поведения в школе с you must and you mustn't

You must wear school uniform. You mustn't use mobile phone at lessons. You must be quite at classroom. You must be in time at school. You mustn't forget your textbook. You must have a letter from your parents if you miss your lessons. You mustn't run in the corridor of your school. You mustn't speak loud.