sharp-tongued       
adjective uk/ˌʃɑːpˈtʌŋd/ us/ˌʃɑːrpˈtʌŋd/
 说话刻薄的
often criticizing people and speaking in a severe way
  He was always fair and just, never sarcastic or sharp-tongued. 他一向公平公正,从不尖酸刻薄。 
 She could be sharp-tongued or sweet-talking, depending on her mood.
 Compare: have a sharp tongue
 - More examples
 - Livingstone is sharp-tongued, witty and ruthless.
 - Sharp-tongued, she can win a war of words with nearly anyone.
 - A confrontation with a sharp-tongued committee chairman followed.
 - His sharp-tongued mother became his role model.
 - Spoilt and sharp-tongued, anyone can tell that she has never been taught to think about other people’s feelings.