The imperative category is the common grammatical category.

祈使是俄汉语共同使用的语法范畴。

The second part is a review of the studies on tense as a grammatical category.

第二部分是概述时态作为语法范畴的研究。

However, the current causative research is neither systematic nor comprehensive. As a result, causative phenomenon has not been established yet as a grammatical category.

但是目前的使役研究缺乏系统性、全面性，导致使役尚未作为一个语法范畴建立起来。