Помогите пожалуйста!!! разобраться с предложениями по теме Модальные глаголы.Заранее благодарна=)

1. You MUST not tell him about it. It's a secret. 2. It looks like rain. You MUST take your raincoats. 3. You MUST not talk so loudly here. 4. In his youth he HAD TO work from morning till night to earn his living. 5. He HAD TO wait at the station till it stopped raining. 6. The secretary informed us when the manager MUST come. 7. They WERE TO leave on Saturday, but because of the delay with their visas they HAD TO book tickets for Monday.(Согласно плану, договорённости, . расписанию они должны были уехать в субботу, но из-за задержки виз им ПРИШЛОСЬ заказать билеты на понедельник) 8. They MUST not tell him anything about it before they get further instructions. 9. He HAD TO leave (ему пришлось, он был вынужден) / WAS TO leave (он должен был уехать в Лондон - согласно плану, расписанию, договорённости. То есть в зависимости от ситуации, оба варианта возможны) for London that night. 10. Must I do it all by myself? 11. It was too late to change their plans and they HAD TO put up) with it. 12. You DON'T HAVE prepare all this work, I will help you. 13. Stay here till she is free. I think you SHAN'T(WON'T) HAVE TO wait) long. 14. We ARE TO conduct a series of experiments this week. 15. Remember that we MUST be // ARE TO be at this place not later than noon.