Japanese by Example
Learning through examples in manga

Don't worry with すんな

俺物語!! » Volume 6 » Page 56

Takeo takes his pregnant mother to the hospital she’s getting close to delivery. Once there, she gives Takeo and his friend Suna a list of things to take care of during her stay.

(かあ)さん:
大丈夫(だいじょうぶ)から心配(しんぱい)すんな
"I'll be fine, so don't worry."

する+な is contracted here to すんな.

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