This is the 11850th most frequent Russian word.
занимающийся
"Engaged in" or "practicing."
The word 'занимающийся' is used as a participle form meaning 'engaged in' or 'occupied with'. It describes the student as actively involved in studying mathematics.
Этот студент, занимающийся математикой, всегда задает интересные вопросы.
This student who is studying mathematics always asks interesting questions.
Here, 'занимающийся' indicates the brother's engagement in physical activity or sports, attributing his involvement in a field.
Мой брат, занимающийся спортом, показал отличные результаты на соревнованиях.
My brother, who is involved in sports, showed excellent results in the competition.
In this sentence, 'занимающаяся' describes the woman as actively involved or engaged in artistic activities, specifically painting.