We should revise our protectionist practices in trade, and promote free trade and competition.
我们应该修改我们的贸易保护主义做法,推广自由贸易和竞争。
Thus one simple fact, a change in the number of bison, had an effect on the whole wildlife chain of the plains.
因此,出现了这样一个简单的事实--野牛数目换的变化对平原的整个野生生物链都产生了影响。