Запишите предложения и подчеркните в них модальный глагол или его эквивалент. переведите. 1. mathematical analysis is used when the facts can be presented in numbers. 2. these researchers will have to use up-to-date materials in their modern apparatus. 3. as the construction of the new plant was an international project, scientists from different countries had to take part in it. 4. the foreman is the person who gives instructions how the work is to be done.