<prompt> unaweza kugeuza matini haya ya swahilikwa kiingereza?watafiti kwenye chuo kikuu cha cornell huko marekani walichunguza kikundi cha watu kwa muda wa zaidi ya miaka 30 na wakapata kwamba wale waliojitolea walikuwa wenye furaha na afya nzuri kuliko wale wasiojitolea.  <response>: researchers at cornell university in the united states studied a group of people for over 30 years and found that those who volunteered were happier and healthier than those who did not. 