①雌蚕蛾释放性外激素
②鸟类的各种鸣叫声
③蚂蚁相互碰撞触角
④乌贼受到威胁时释放墨汁
⑤遇到猎豹追捕，瞪羚会急转弯
⑥狗一路走一路撒尿．
The fact that lets artists down is that Peking Opera, a 200-year-old art form, is losing popularity.
