5 is divided into 1 and 4,4 and 1. 5 is divided into 2 and 3, 3 and 2.
6 is divided into 1 and 5,5 and 1 6 are divided into 2 and 4, and 4 and 2 6 are divided into 3 and 3.
……
such
Don't be divorced from the real thing at first. Sticks, chess pieces, building blocks, candy bars, etc. The more patterns, the better, abstract from different objective reality, initially establish the concept of number and cultivate the feeling of number)