No, there is no problem of concentration in the math book published by Beijing Normal University, but there is one in People's Education Edition. Many people buy books that teachers ask them to buy and find that they have concentration problems and have never studied them. In that case, the book you bought is the People's Education Edition.

Of course, I have confirmed many times that there is no problem of concentration, so I don't have to worry about failing the concentration test in the exam of the West Normal University Edition ~ ~ ~