That's right. Although there have been arguments about problems outside the outline in the past, others are just scratching the edge and have not completely deviated from the outline. The contents of the outline must be read carefully, but there is no need to be too dogmatic. For example, you can choose some typical examples and after-school questions, and others can be skipped. But one thing is that the theorems in it are all positive, and you must scrutinize them yourself. Remember!