分类：教育/科学-外语学习
问题：英语Humanfacialexpressionsdifferfr 
Human facial eressions differ from those of animals in the degree (to which )they can be controlled on purpose .这道题解释一下，谢谢
回答：人类的面部表情不同于其它动物.因为他们能故意改变面部表情