<prompt> Translate the following text to EnglishNi lazima tujue, alisema kwa utulivu, na Tuppence alihisi kwamba kama yeye alikuwa Bw. Brown, hangeipenda sauti ya maneno hayo sahili.  <response>: We must find out, he said quietly, and Tuppence felt that if she was Mr. Brown she would not like the tone of those simple words. 