to put it bluntly 直言不讳
To speak in a very direct and abrupt manner, perhaps without being tactful or sensitive.
I only corrected my sloppy dressing habits when my boss decided to put it bluntly and tell me that my careless appearance would hurt my future career.
老板决定直言不讳跟我说,不注意外表会影响职业前途,这时候我才改正了不修边幅的习惯。