1, the left hand represents ten digits, and the right hand represents one digit.

2. The big finger stands for 5 (equivalent to the upper bead of the abacus), and the other four fingers stand for 1 (equivalent to the lower bead of the abacus).

3. Add and subtract 5 (4+3)A, apply for 4 fingers (non-thumb) B with the right hand, apply for thumb and take off the tail. If the ring finger (2 refers to 5-3) is 1(4 refers to 5- 1).

4. Break 10 addition and subtraction.

5, practice makes perfect, mathematics is practice, there is no other shortcut. Just memorize the decomposition and combination sum of numbers within 10, add and subtract 10 and subtract 10.

6. Teaching memory and discussion can be mainly carried out through icons. From the table, we can clearly find the laws between numbers and between numbers.