The purpose of this paper is to examine tense category and aspect category in past high school grammar textbooks. In chapter Ⅱ, we examine terms and concepts of tense category and aspect category. In chapter Ⅲ, we examine tense system and aspect system. The system of time expressions in prefinal endings change from ``the system of pluperfect, past, present, future tense`` to ``the system of present, past, future tense``. The system of time expressions in adnominal endings change from ``the system of past, past imperfect, present, future tense`` to ``the system of past, present, future tense``. The system of aspect expressions is the progressive aspect and the perfective aspect. And then we analyze the meaning of tense expressions and the meaning of aspect expressions. In chapter Ⅳ, we examine learning activities of tense category and aspect category.