Tariffs and quotas are the two major forms of trade restrictions ( or protectionism ) , which interfere with the free flow of trade among nations.是什么意思_Tariffs and quotas are the two major forms of trade restrictions ( or protectionism ) , which interfere with the free flow of trade among nations.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句