Alright, ready to do some subtraction? We're taking 7923 and subtracting 1000 from it.

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

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

Step 3: We'll start by subtracting the digit 0 and the borrow 0 from 9 in column 3 and get 9.
9 is the next digit of our result.

Step 4: We'll start by subtracting the digit 1 and the borrow 0 from 7 in column 4 and get 6.
6 is the next digit of our result.

So, 7923 - 1000 = 6923.