It is not difficult to tour Qiu Guanyuan. Circuit is a book published by Higher Education Press 20 1 1. The writer is Qiu Guanyuan. Its main goal is to adapt to the reform of the training scheme and teaching content system of electronic and electrical information professionals and the rapid development of higher education. The course "Fundamentals of Circuit" is not difficult or difficult. To grasp the key points, we must master several theorems. Capacitance and inductance are more difficult, so it will be more useful to master them and learn engineering in the future.