Let's break this down. We're going to add 208 and 783 together.

Step 1: We'll start by adding the digits 8 & 3 in column 1 and get 11.
We'll write down the last digit 1 and carry the 1 to the next column.

Step 2: We'll start by adding the digits 0 & 8 in column 2 and get 9.

Step 3: We'll start by adding the digits 2 & 7 in column 3 and get 9.

So, 208 + 783 = 991.

