To tell you the truth, when I went to the library in high school with my roommates we would usually waste timeended up goofing off.

• 无聊的事开玩笑。我才不会忘掉那次去看电影的事呢。那几个中学生往银幕上扔糖果，真是太无聊了，他们还以为好玩呢。