What is the nine squares?

A square, in which two horizontal lines and two vertical lines are made to divide the square so that it becomes nine small squares of equal size, is commonly known as the nine squares

Application, as far as I know, should be Taijiquan, the Chinese boxing is more concerned about the footwork, which means that the place where a person is standing as the middle of the nine squares, and how to move the feet is a matter of principle

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