How do I prevent recommendations from being perceived as ads?

I have an app for learning Chinese that keeps track of the vocabulary the user knows.

Based on this vocabulary, it recommends videos to watch that will be comprehensible to the user. In each entry it will show a corresponding estimate like "90.963% comprehensible".

At the end of a reading lesson where the users has learned new vocabulary, it will also show recommendations after the end-of-lesson summary:

I have gotten less engagement on these recommendations than I expected, and it seems that one reason for this is that some users perceive these recommendations as advertisements. Rather than realizing the usefulness of the feature, they automatically ignore them because of the ad-like appearance.

(I learned of this fact after one user left a review complimenting, among other things, the unobtrusiveness of the ads. The app does not contain any ads.)

Is there a better way to present these recommendations to the user in a way that they will realize that they contribute to their learning, rather than perceiving them as advertisements?