This study proposed a three-tier test to help students learn English grammar. To reduce students' anxiety, game-based learning was incorporated into the three-tier test, where personalization was also implemented to accommodate students' different needs. More specifically, we developed a Personalized Entertaining Three-Tier Test (PET3), which consisted of the three-tier test, game-based learning and personalization. On the other hand, diversities exist among learners, especially prior knowledge. To this end, this study aimed to provide the complete understandings of the effects of prior knowledge in the PET3 context, in terms of test performance, task performance, learning behavior and gaming behavior. Regarding test performance, high prior knowledge learners (HPK) performed better than low prior knowledge learners (LPK). Regarding task performance, HPK was superior to LPK in two aspects, i.e., the reasons of the main questions and advanced questions, while LPK performed better than HPK in the aspect of the review questions. Regarding learning behavior, HPK and LPK favored to use different hints. Regarding gaming behavior, HPK tended to be a winner while LPK had a tendency to be looser. Based on these findings, we developed a framework, which could help designers and instructors to know the preferences of diverse learners.