For the dry goods in the teaching aid, it also depends on whether the students can effectively absorb and transform. Dry goods are too dry, the content is boring, and students won't read it at all. After water, it is not worthy of the name, and students' ability will not be improved after practice.
Therefore, there are many dry goods in a teaching assistant, and which dry goods are delicious and delicious is the most important.
Personally, I am deeply impressed by the exercise books that I have contacted and studied carefully. It doesn't matter if I incorporate "dry goods" into flexible topics, because when I see the footer, I will find that these contents just echo the thinking reflected by the topic on this page, so that students who don't understand the topic can understand it, and students who know the topic can be more impressed.