19 19 years of good friends,

Hand in hand,

3737 is so close,

Let's go together, four, four, six, six.

Make a pair of hands in half.

One plus nine, ten tadpoles,

Two plus eight, ten old ducks,

Three plus seven, ten old hens,

Four plus six, ten golden monkeys,

Five plus five, ten big tigers.

See 9 and think of 1,

See 8, think of 2,

Seeing 7 and thinking of 3,

See 6, think of 4.

See Osuka decimal,

First, change the position of two numbers and calculate the ballad mathematically (make up ten songs).

Extended data:

Carry addition within 20

Children should keep in mind that the methods of "9-to-0/","8-to-2", "7-to-3", "6-to-4" and "5-to-5" are simple and easy, and the thinking process includes "looking at large numbers (looking at large numbers), dividing decimals (looking at decimals), doing ten and adding even numbers".

Ten plus one method is very useful within 20. Learn the following from the teacher ~

Son, let's calculate first. 10+ 1=? ,9+8=? Which do you like better, baby? Must be the first one who likes teachers ~ why is this?

Because 10 plus a few equals more than ten, this is easy to calculate.

But in the real calculation, not all the questions have 10, which is not easy to calculate. It doesn't matter, there is no 10, we just try to get 10.

Now let's count 9+8. Who can add up 10? 9 or 8 can add up to 10, and we will add up to 9 to 10. 9 is 10 of 1, so let 8 give 9 a 1, leaving 7.

1 and 9 are good friends, and good friends should hold hands first. 9+ 1= 10, plus 8, the remaining 7, 10+7 = 17. 8+7= 8 is closer to 10, so make 8 10. 8 is 2 of 10, 7 gives 8 a 2, leaving 5. Say good friends first, and add the remaining 5,8+7 =15.