niuniu said to herself，一不小心滑到水盆里出不來了，為什么呢？niuniu thought for a long time， niuniu looked up to see the moon in the sky，水盆中的月亮，天上到處都是亮晶晶的星星，想起光學知識，大自然真奇妙，她恍然大悟，summer night，突然，妞妞百思不解，” niu niu finds that there is also a moon in the water basin. niu niu is s