2月15日，上海浦东新区一商场里安装的“钢琴阶梯”，市民走上任意一个台阶都会对应“弹出”一个悦耳的音符。[中国网图片库 王冈 摄]
The "piano stairs" that can produce melodious sounds are installed at a large shopping mall in the Pudong Area of Shanghai on Feb. 15, 2016. [Photo by Wang Gang/phototock.china.com.cn]