Personally, the poor foundation is mainly due to the familiarity of textbooks. It is also good to get some papers or workbooks to do. We should start with the basics to increase the number of questions and do them.
Look at the basics. Wang Houxiong must not waste a long time obsessing over its concept.
There are still some questions that are a little difficult or too difficult, and have no reference value. You should screen them yourself.
In fact, I think it will be very helpful for you to carefully sort out the knowledge points in the future. Really, don't feel too little.
Thank you for adopting it.