Подчеркните в каждом из них модальный глагол или его эквивалент. 1. wolfgang’s son johann was to retrace practically the same path that gauss had followed. 2. the problem how electricity could be produced had faced the scientist volta, and the device with which he solved it, is named after him. 3. in 1816 davy wrote: “ i have made very simple and economic lanterns, which may be useful to the miner.” 4. having discovered the electrical properties of semiconductors scientists were able to use them for making devices small in size.