First, don't abdicate, look at one place first, one place is reduced to writing at the back, and ten places are reduced to writing at the front.

Second, if the unit is not enough, borrow, click the borrowing point, and use the formula (borrowing number, complement, remainder, writing number). The borrowing number is the borrowing point, and the complement is the complement of the decimal (9-1; 2-8; 3-7; 4-6; 5-5), the remainder is the number of units added by the complement. Finally, write the numbers.