OK, let's do this. We've got 43476 and 40855, and we're subtracting the second number from the first.

Step 1: We'll start by subtracting the digit 5 and the borrow 0 from 6 in column 1 and get 1.
1 is the first digit of our result.

Step 2: We'll start by subtracting the digit 5 and the borrow 0 from 7 in column 2 and get 2.
2 is the next digit of our result.

Step 3: We'll start by subtracting the digit 8 and the borrow 0 from 4 in column 3 and get -4.
We add -4 to 10 and get 6 as the next digit of the result.

Step 4: We'll start by subtracting the digit 0 and the borrow 1 from 3 in column 4 and get 2.
2 is the next digit of our result.

Step 5: We'll start by subtracting the digit 4 and the borrow 0 from 4 in column 5 and get 0.
0 is the next digit of our result.

So, 43476 - 40855 = 2621.