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Hellen Petrovskaya
Помогите выполнить задание по английскому.
Помогите пожалуйста решить задание. Нужно функцию инфинитива в следующих предложениях:
1. They were the first to prove it.
2. The purpose of this book is to describe cetrain properties og metals.
3. The experiment to be carried out is of great importance for our research.
4. They promised to supply us with the necessary equipment.
5. To convert chemical energy into electrical one we must use an electrical cell.