Some notes can be studied with their facets reordered. For example, if you are learning Spanish, you might have one facet with an English word, and a second facet with the Spanish word. You need to learn what the Spanish word is that corresponds to a particular English word, but also the opposite, namely, what the English word is for a given Spanish word.

Studies allows you to stipulate which facets in a note can be used as the prompt/question. In this example, stipulating that both the English and Spanish facets can be used as a prompt will mean you will see both combinations in study study sessions.