<prompt> Translate the following text to EnglishKaribu nusu ya maili ya darasa la kwanza ni kazi ya pamoja na sehemu kubwa zaidi ya A4 ya kawaida ni kazi ya pamoja au ina mahitaji ya maandalizi ambayo yanahusisha kazi ya barua.  <response>: In the United States, almost half of the First-Class mailstream is workshared and an even larger portion of Standard A4 is either workshared or has preparation requirements that involve work the mailer must do. 