cause of :起因;属…原因
We are investigating the cause of the accident.
我们正在调查意外事件的原因。
carry out :实行,执行,贯彻,进行(到底);开展:;完成;实现
He would let her manage everything and carry out all her notions.
他会让她安排一切,实现她所有的想法。
at the time :在那时,那时候
At the time, printing itself was not a new idea.
在当时,印刷术本身并不能算是一个新想法。
Severe storm :暴风;强烈风暴
The sky lightened after the severe storm.
狂风暴雨之后天空变亮了。
tear down v. 扯下;诋毁;拆卸;逐条驳斥
So history reminds us that walls can be torn down.
所以历史提醒我们那些墙是可以被推倒的。