Through an existing model, mathematical conclusion, physical experiment and physical phenomenon, through enumerating and simplifying, or giving relevant information, we can think with textbook knowledge, and sometimes simply turn it into an ideal experimental topic or a data topic, often highlighting the details because of many elements.

It is common to get stuck in a transitional link in the process of solving problems. At this time, you can admit the intermediate conclusion first, and then push it backwards to see if you can draw a conclusion. If there are two questions and the (1) question doesn't make sense, you can regard the (1) question as "known", do the (2) question first and jump to the answer. When the problem of positive thinking is blocked, using the method of reverse thinking to explore new ways to solve the problem can often make breakthrough progress.

"Retreat for progress" is an important problem-solving strategy. For more general problems, if the problems can't be solved at the moment, then we can retreat from the general to the special, from the abstract to the concrete, from the complex to the simple, from the whole to the local, from the parameters to the constant, and from the strong conclusion to the weak conclusion. In short, retreat to a solvable problem, and solve the "special" by thinking and inspiring thinking, so as to achieve the purpose of solving the "general".

When the positive thinking of a problem is blocked, using the method of reverse thinking to explore new ways to solve the problem can often make breakthrough progress. Push forward if you have difficulty, and push back if you directly prove that you have difficulty.