plain-spoken       
adjective uk/ˌpleɪnˈspəʊ.kən/ us/ˌpleɪnˈspoʊ.kən/
 直言不讳的,说话坦率的
saying clearly and honestly what you think without trying to be polite
  He's very plain-spoken. 他说话很直白。 
 Part of her appeal was that she was plain-spoken and straightforward. 说话直截了当是她吸引人的一个特点。 
 See: plain speaking
 - More examples
 - Coolidge was plain-spoken and never denounced his opponents.
 - The plain-spoken president is known for taking positions and steadfastly sticking to them.
 - Joe, in his plain-spoken way, said this sounded a lot like socialism.