Some funny words about study should not be too long?

After class, the teacher said, "Whoever answers my first question doesn't have to answer the second question." Xiaoming threw down his schoolbag. The teacher asked, "Who threw down his schoolbag?" Xiao Ming said, "It's me!" The teacher asked, "Why did you throw it down?" Xiao Ming said, "I have answered one of your questions. You said you didn't have to answer your first question. "