What does the first "ten plus ten, one plus one" mean? For example: 36+45= () Here, 36 is regarded as 30 and 6, and 45 as 40 and 5, so 30+40=70 (ten plus ten) 6+5= 1 1 (one plus one). The last 70 plus 1 1 equals.

The second type: "first add ten, then add one" is also an example of 36+45= (). Generally, the second addend is decomposed into "ten" and "several" (dozens and several), that is, 45 is regarded as 40 and 5, first 36+40=76 (first add ten), then 76+5 = 86.

To sum up, there are two ways to add two digits orally. The first one is: ten plus ten, one plus one. The second type: first add ten, then add one. (Either way, there is only one purpose, so it is good for students to understand. )