The material are used in magnetic circuit system of the electrical machines, the iron core are made of these materials. The most commonly used materials are silicon steel , cast steel and steel plate. it is______
【简答题】第二节 完形填空(共20小题,每小题1.5分,满分30分) Be careful of those who use the truth to deceive (cheat). When someone tells you something that is true, but 36 important information that should be included, he can ...