This is the 2254th most frequent Russian word.
занимались
"Engaged in" or "were occupied with."
In this sentence, "занимались" reflects involvement in a specific activity, showing its use in past continuous tense.
Мы занимались спортом весь вечер.
We were engaged in sports all evening.
Here, "занимались" is used to indicate the process of dedicating oneself to the activity of studying.
Когда вы занимались изучением этого материала?
When were you engaged in studying this material?
This usage of "занимались" demonstrates its application to indicate the undertaking of a complex task or duty.