名著阅读：读下面的小诗，回答问题。
                                                                                                 小小的花，
                                                                                                 也想抬起头来，
                                                                                                 感谢春光的爱——
                                                                                                 然而深厚的恩慈，
                                                                                                 反使她终于沉默。
                                                                                                 母亲啊！
                                                                                                 你是那春光吗？

   22时15分用普通计时法表示是(   )。