The purpose of the topic is to learn the composition, addition and subtraction of 10. The key is to treat 1, 2, 3 and 4 cycles *** 10 as a picture.

The following black three: 3+7 =107+3 =1010-3 = 710-7 = 3.

Black matrix 4: 4+6 =106+4 =1010-4 = 610-6 = 4.

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