1, according to the leftmost column, the bottom is (45- 19-22)=4.

2. The sum of the two penultimate ones in the second column of the left number is 19-4= 15, so the third one in the second column of the left number is 45-6- 19- 15=5.

3, so the sum of the three numbers on the right of the nine squares in the upper left corner is 20-5= 15.

4, so the sum of the two numbers in the lower right corner of the nine squares in the lower left corner is 45-15-11-3 =16.

5, it won't be 8+8, it can only be 7+9 or 9+7, and the 9 squares in the middle can be completed no matter which one is below.

As shown in the figure: