Перепишите следующие предложения; подчеркните в каждом из них модальный глагол или его эквивалент. Переведите предложения на русский язык.
1. Businessman should learn how to control their actions and feelings.
2. The amount of electron emission that can be obtained from an incandescent filament or cathode depends on a number of factors.
3. The modulated carrier must be sent out into space by the antenna.
4. Payment in foreign trade may be made in cash and on credit.
5. Semiconductors can be distinguished both from metals and insulators.