He firmly believes that education and a country's economic development are key factors to progress.
他坚信教育和一个国家的经济发展是通向进步的关键因素。
There are two key factors behind this trend.
这一趋势背后有两个关键因素。
Among the key factors behind this growth were increased agricultural productivity and an expansion of trade.
这种增长背后的关键因素是农业生产率的提高和贸易的扩大。