Thank you for viewing. I am selling a set of two books: the 2020 edition of the Psychology Certification Official Problem Collection and the 2019 edition of the Psychology Certification Basic Keywords. I used them and then stored them on a bookshelf for about 6 years. In the Psychology Certification Basic Keywords, I have highlighted "Development/Education," "Social/Emotion/Personality," and "Clinical/Disability" with a marker, and the dates are also written. In the Official Problem Collection, I have also highlighted and checked the answer explanation sections for "Development/Education," "Social/Emotion/Personality," "Clinical/Disability," "Industrial/Organizational," and "Health/Welfare," and the dates are also written. There are no markings on the problem sections themselves. Please understand this before purchasing. The items will be packaged in waterproof packaging and will be posted in a mailbox.