Why use the perfective "остаться" on one hand and the imperfective "оставаться" on the other?

Question

>Woman: Я могла бы **остаться** здесь навсегда.>Man: Так **оставайся**.I wonder why you need to use the perfective "остаться" on one hand and the imperfective "оставаться" on the other, even though they both refer to the same action of the woman staying in the same place.

Answer 1

It's an interesting question.. "Я могла бы остаться" means one time to make a decision and stay. It's perf, of course. When the man is saying "оставайся" it could be permission to act when the speaker doesn't necessary care whether you do so or not. We use imperceptive in these situations. If he really cares he would say "останься здесь, останься со мной." Compare these examples:

Можно посмотреть фотографии? - Смотрите ( мне всё равно, я не против)

Посмотрите на эти фотографии ( я хочу, чтобы вы посмотрели)