Yotsuya Otsuka Yojun Series Japanese Language Arts, 4th Grade Most Difficult Problem Collection, Volumes 1 & 2 Volume 1: No writing, answer sheets included, name written (will be erased or cut out) Volume 2: Unused (still in plastic wrap) These books were used at a cram school, so I will sell them to someone who doesn't mind minor imperfections. For students who will finish in 2026.