Answer:
The forgetfulness that occurs between classes is probably the result of lack of revision.
Step-by-step explanation:
Whenever the teacher teaches us a new subject, we should review all that has been taught. The importance of reviewing what we study exists because we cannot keep everything we study. In fact we can hardly remember anything if we do not have a review scheme already planned. For this reason, we can conclude that the forgetfulness of the students exposed in the question is a result of the lack of revision.
It is important to review each one we study countless times and in different ways. Ideally, the review should be done, if possible, every day. Even if it is fast, it is important to always take a look at what has been studied, especially the subjects that you find difficult.