2.  词汇讲解：activity的意思是thething people do. 从意思上和action差别不大，但是搭配的差别很大：

例句1：There’s a flurry of activity whenevera star emerges on the scene. 明星出现的时候，就会出现骚动。

    再如，beinvolved in criminal activities(或者illegal activities)涉嫌参加犯罪活动, participate in subversive activities参加颠覆活动, （或者terrorist activity恐怖活动）,  take part in extra-curricularactivities参加课外活动（或者leisure-time activities业余活动, social activities社会活动, outdoor activities室外活动, cultural activities文化活动, 或者There were a burst of volcanic activities近期火山运动频繁 

    写作中，到似乎是activity更常用些，还经常做复数使用。