This is the 2509th most frequent Russian word.
происходят
"Происходят" means "are happening" or "occur."
The word 'происходят' here refers to events taking place or occurring.
События сейчас происходят быстро.
Events are happening quickly now.
In this sentence, 'происходят' is used to describe changes that are occurring spontaneously.
Многие изменения происходят внезапно.
Many changes happen suddenly.
Here, 'происходят' refers to actions or phenomena affecting the subject in a specific manner.