They're trying to achieve satisfaction through their mouth of a sort they didn't get in this very early stage of development.

他们想通过这种口腔运动,来获得本该在口腔期获得的满足感。

耶鲁公开课 - 心理学导论课程节选

It wants to eat, drink, pee, poop, get warm, and have sexual satisfaction.

本我追求吃喝拉撒，保暖，和性欲的满足。

耶鲁公开课 - 心理学导论课程节选