不用 (don't need to)

"No need"

• need not不用bù yòng = "don't need to / no need to".
• You're welcome不用谢bù yòng xiè = "you're welcome (no need to thank)."
• It's the negative of want / will / need要yào / to need需要xū yào here.

Subj + need not不用bù yòng + Verb Phrase

• need not不用bù yòng waves away an unnecessary action.

you你nǐdon't need to不用bú yòngworry担心dān xīn。

• need not不用bù yònganxious担心dān xīn = "no need to worry."

need not不用bù yòng vs don't不要bú yào

• need not不用bù yòng = unnecessary; don't不要bú yào = don't (a prohibition).

Recap

Read the full reference: HSK 4 grammar — Auxiliary verbs.