Divide 14 into 4+ 10, 10-9= 1, and add 4+ 1=5. The jingle can be recited: a dozen MINUS 9, a few plus1; A dozen MINUS 8, a few plus 2; A dozen MINUS seven, a few plus three; A dozen MINUS six, a few plus four; A dozen MINUS five, a few plus five; A dozen MINUS 4, a few plus 6, a dozen MINUS 3, a few plus 7; A dozen MINUS 2, a dozen plus 8, a dozen MINUS 1, and a few plus 9.
Remember the "ten-point method": 19 19 are good friends, 2828 is holding hands, 3737 is really close, 4646 is walking together, and 550 is a pair of hands.
Borrowing ten is a calculation method used in the subtraction of abdication within 20. The principle is to use the "borrow ten method" to transform the mathematical algorithm within 20 into the familiar topic of 10 bit subtraction in the form of abdication subtraction, which is a simple algorithm.
When subtracting 9 from 14, firstly, considering that it is not enough to subtract 9 from 4 cells, we borrow 10 from ten digits to subtract 9 from 10 to get 1, and then add 1 to 4 cells to be equal to 5.
References:
Pre-school Mathematics Special Exercise: Borrowing Ten Methods-Baidu Encyclopedia