翻译：你还保证今后会帮助她做一些家务活

you also ensure that you will help her do some housework

you also guaranteed that you would help her to do some housework (最精确)
一楼的ensure用的不恰当，而且不应该是现在时，应该是过去式。“还保证”结合整句的上下文应该是过去保证过的事情。

二楼的should用的不恰当。本句话是过去式的可能性最大。例子：“昨天”你还保证今后会帮助她做一些家务。

而如果用现在时的话应该是：你“应该”还保证今后会帮助她做一些家务。

you should also guarantee that you will help her with some housework in future.