“丁零零……”欢快的下课铃声响了,同学们都如释重负地合上了书。老师对我们意味深长地看了一眼,便大步流星地走出了教室。顿时,我们从乖乖兔变成了大灰狼。而就在这时,几种“疯”在我们班上出现了,现在我们就来看看吧! “Ding zero zero ... ” cheerful get out of class bell ringing, the students are relieved to close the book. The teacher took a meaningful look at us and walked out of the classroom. Suddenly, we have become a wolf from the obedient rabbit. And just then, several “crazy” appeared in our class, and now let’s see!