An aspect is a quality of a verb that expresses the internal temporal flow, or continuity, of an action. In Common Standard Zekaisivarsi, there are three formal aspects: perfective, imperfective, and jeshae.
The perfective aspect denotes actions that are simple, that is, one performs an action a single time and completes it.
A common example is isai, "to name; to call, address".
The perfective is also used in the past tense and is similar to the perfect or simple past in English. It is used to indicate completed actions or acts considered without internal structure.
The imperfective aspect denotes action with internal structure or that are not completed, and is similar to the English be [verb]ing structure. It typically uses internal reduplication.
Take the verb saih. When it is reduplicated, it becomes sa’aih “to learn, to come to know”.
The jeshae aspect denotes actions without regard to any internal structure and gives rise to a verb form called the pure jeshae. It is often used with verbs of mental actions.
Ospia du doie aur. I believe/opine that it is wrong for me to kill.
This does not emphasize the internal structure of ospia but rather the action itself, the action qua action.
A form called the pure jesha is used in narratives.