<prompt> Translate the following text to EnglishLazima kujua kitu cha kuwa matangazo kama wewe alifanya? Yeye leaned mbele kidogo, sauti yake uchovu uliofanyika hint ya ushawishi.  <response>: You must know SOMETHING to have advertised as you did? He leaned forward a little, his weary voice held a hint of persuasiveness. 