夏天的天气是孩儿脸,说变就变。刚才还是晴空万里,一刹时就电闪雷鸣,大雨倾盆。风雨停了,天气又转睛。“老师,快看,那是什么?”孩子们稚声稚气地在发问。我顺着他们手指的方向望去——哦,原来天上挂着一条美丽的彩虹:赤、橙、黄、绿、蓝、青、紫,煞是好看。彩虹慢慢地消失了。孩子们多么希望再看到彩虹。“是谁把彩虹挂在天上的,那么好看?”“彩虹为什么总是弯弯的呢?”他们七嘴八舌地议论着。我怎么回答呢?他们还小,用光的色散、光的折射和反射的道理解释,他们听不懂。第二天是星期天,我在棉田用喷雾器洒农药。突然,一道彩虹在我眼前一闪而过,我觉得奇怪,同时怀疑到自己的眼睛是不是看错了。可是, Summer weather is a child’s face, that change becomes. Just still sunny skies, a flash of lightning thunder, heavy rain. The weather stopped, the weather turned around again. “Teacher, let’s see, what’s that?” The children asked naively. I looked down their fingers - oh, a beautiful rainbow hanging in the sky: red, orange, yellow, green, blue, green, purple, is really good-looking. The rainbow slowly disappeared. How children want to see the rainbow again. “Who is the rainbow hanging in the sky, so nice?” “Why do the rainbow always bend?” They talked in rumors. How can I answer them? They are still young, explained by the dispersion of light, the refraction and reflection of light, and they can not understand it. The next day is Sunday, I sprinkle pesticides on the cotton field with a sprayer. Suddenly, a rainbow flashed before my eyes, I felt weird, at the same time wondering whether my eyes were wrong. but,