This is the 679th most frequent Vietnamese word.
đừng
"Đừng" means "don't" or "do not" (used to express prohibition or negative command).
Here, 'đừng' is used as an imperative negative to caution or forbid an action.
Đừng đi vào khu vực đó.
Do not go into that area.
In this context, 'đừng' is employed to give a gentle reminder or advice against forgetting.
Em đừng quên làm bài tập nhé.
Don't forget to do your homework.
'Đừng' here is used to ask someone to refrain from an action, specifically to maintain a quiet environment.