不知所措

On the HSK 7-9 vocabulary list, at CEFR level C1.

bùzhīsuǒcuò ㄅㄨˋ ㄓ ㄙㄨㄛˇ ㄘㄨㄛˋ

    • not knowing what to do (idiom) at one's wits' end
    • embarrassed and at a complete loss

Character by character

Sources