Salesperson Level 2 textbook, problem set, and explanations are easy to understand, with red sheets included. I studied for about a month using these two books and passed. I started studying from Level 2, but these books were sufficient, and I scored over 70 points in each of the five sections. The writing is in orange, so you can use the red sheets to hide it. There is probably no writing in the textbook. I will remove the sticky notes before shipping.