How do i write this in a expression the number of pencils (p) after aaliyah has given 4 away

When writing an expression, you first want to identify how many terms you will have in the expression.

pencils (p)

4 away

You will have two terms.

She gave 4 away. She has four fewer pencils. That will be subtraction.

p-4

I hope this helps!
~kaikers