One by one, one by one, until 1999, then 222 to 4,236, until 298, then 339,3412, until 3927, and so on, then 446 columns, 5525 columns, 6636,7749.

There is a rule in this method, that is, the number of digits in the vertical column increases gradually, which can help memory.

2. Turn your back to one side

On the rampage for the first time, one sentence at a time; The second sentence is two sentences, one sentence is two sentences, and two sentences are four sentences; By analogy, the first few lines are only a few sentences, and the last nine sentences range from 199 to 998 1. There is another rule in this method. In the first few lines, the last sentence is a few more than the previous one.

Step 3 twist your head

Recite one or two to get two, and then recite two or two to get four. At this time, turn it down and recite two or three to get six, and two or four to get eight until 298; Then go back to one three to get three, two three to get six, three three to get nine, and then turn down to three four twelve until three nine twenty-seven; And so on, go back to a four, get a four, and then turn.

One of the characteristics of this recitation is that there are nine sentences in the formula from one to nine, and several formulas will gradually increase.

Extended data:

Characteristics of Jiujiu Watch

General 1 and 99 tables only use 9 numbers from 1 to 9.

2. Jiujiu table contains the commutativity of multiplication, so only 8972 is needed, and "9872" is not needed. 9 times 9 has 8 1 product, and the 99 table only needs 1+2+3+4+5+6+7+8+9 =45 product. In the Ming Dynasty, abacus also had 99 tables with 8 1 product. The 99 table of 45 items is called small 99, and the 99 table of 8 1 item is called big 99.

3. The shortest multiplication table in the ancient world. Maya multiplication table must have 190, Babylon multiplication table must have 1770, and Egypt, Greece, Rome, India and other countries must have infinite multiplication tables; Only 45/8 1 item is needed for the 999 table.

4. There is rhythm when reading aloud, which is convenient for memorizing the whole table.

5. Jiujiu watches have existed for at least 3000 years. It was used for calculation from the Spring and Autumn Period and the Warring States Period, and was improved and used for abacus in the Ming Dynasty. The 99 standard is also the basic skill of elementary school arithmetic. People generally describe those who are good at calculating, calculating and planning as having a career in mind.