People who live in developed countries that declare themselves as very happy, like Switzerland, Denmark and Canada, or those which describe themselves as unhappy, like Italy, Greece, and Spain?
是在已發展國家中人人都說自己過著快樂生活的人,比如瑞士、丹麥、加拿大;還是那些表示他們過得不開心的人,比如義大利、希臘、西班牙人?