【英语活动】__ [第五天]一个月帮你攻克考研词汇--截止日期6月30日

Essentially,a theory is an abstract ,symbolical reprensentation of what is conceived to a reality.
  从本质上不讲，理论是对事物真相的抽象的，符号化的概括。

Long before children can speak and understand a  language ,they communicate through
facial expressions and by making noise.

儿童在说和理解一种语言之前,他们是通过面部表情和声音来交流的.

Thanks to modern irrigation,corps now  grow abundantly in  areas , where once nothing but cacti and sagebush could live .

幸亏有现代灌溉方式，地里庄稼长势喜人，而之前这仅能长些仙人掌和山艾树。