<prompt> Translate the following text to EnglishKwanza, barua inaweza kupata kwamba barua presorted na au barcodes zip kupitia mfumo bila kuchelewesha wakati barua nyingine, ambayo inahitaji tahadhari zaidi posta, ama ni kucheleweshwa au ni unpredictable.  <response>: First, a mailer could find that mail presorted andor barcoded zips through the system without delay while other mail, which needs more postal attention, is either delayed or is unpredictable. 