Write an expression for the sum of 𝑚 and four.
To write this expression, we’ll need to know what the word “sum” means. The sum of two digits is found by using addition, by adding them together. And what are we adding together? 𝑚 and four, 𝑚 plus four. An expression for the sum of 𝑚 and four would look like this: 𝑚 plus four.