zhège / yánjiū / zhǔyào / jùjiāo / yú / dì yī shì jiè / yǔ / dì sān shì jiè / zhījiān / de / jīngjì / chājù

这个研究主要聚焦于第一世界与第三世界之间的经济差距。

This research focuses mainly on the economic gap between the First World and the Third World.