The expression in the image is:

$9m - 5n + 14 + m - 2n - 7$

Let's simplify it step by step:

1. Combine like terms involving $m$: $9m + m = 10m$

2. Combine like terms involving $n$: $-5n - 2n = -7n$

3. Combine the constants: $14 - 7 = 7$

Now, putting everything together, the simplified expression is:

$10m - 7n + 7$

Would you like any additional explanations or further steps on this? Here are some related questions:

1. How would you simplify expressions involving more variables?
2. How do constants affect the behavior of linear equations?
3. Can you combine unlike terms in algebraic expressions?
4. How do you factor expressions like this one?
5. How would this expression change if one variable were given a value?

Tip: Always group similar terms together when simplifying to avoid mistakes.