Перепишите следующие предложения, подчеркните в каждом из них модальный глагол или его эквивалент; предложения переведите на язык. 1. they had to stay at home because it was raining. 2. if we are allowed we shall take some exams in advance. 3. the experiments are to clarify this point of view. 4. he must ring you up. 5. i won’t be able to help you. 6. you can get all the necessary books in the library.