1. The swift growth of this merchant marine diversified the northern colonial economy and made it more self-sufficient. 这艘商船的迅速发展使北方殖民地经济多样化，使其自给自足的能力更强。
2. After 1815 improved transportation enabled more and more western farmers to escape a self-sufficient way of life and enter a national market economy. 1815年以后，交通的改善使越来越多的西方农民摆脱了自给自足的生活方式，进入了国家市场经济。
3. The country is totally self-sufficient in food production. 在粮食生产上，这个国家完全做到了自给自足。
4. This enabled the country to become self-sufficient in sugar. 这使得该国在食糖方面变得自给自足了。
5. Although she had various boyfriends, Madeleine was, and remains, fiercely self-sufficient. 尽管有过各种各样男朋友，马德琳过去和现在一直都非常自立。
