SCIENCE FACTS ABOUT ENERGY

LIGHT

-One of the most familiar and important forms of energy is light. Nothing is visible to humans when light is totally absent. But light is even more important for other reasons. Many scientists believe that millions of years ago lightfrom the sun triggered the chemical reactions that led to the development of life on Earth. Without light the living things now on Earth would be unable to survive. Light from the sun provides energy for life on Earth. Plants change the energy of sunlight into food energy. When light rays strike a green plant, some of their energy is changed to chemical energy, which the plant uses to make food out of air and minerals. This process is called photosynthesis. Very nearly all living organisms on Earth depend directly or indirectly on photosynthesis for their food energy. 


-Light travels in a straight line.


Reflection-Reflection occurs when a light ray hits a surface and bounces off. The angle at which the ray hits the surface is equal to the angle at which it bounces off. If the surface is made very flat and smooth by polishing, all the light rays bounce off in the same direction. 


Refraction and Dispersion-Light travels in a straight line as it passes through a transparent substance. But when it moves from one transparent material to another of different density—for example, from air to water or from glass to air—it bends at the interface (where the two surfaces meet). This bending is called refraction. The amount, or degree, of refraction is related to the difference between the speeds of light in the two materials of different densities—the greater the difference in densities, the more the speed changes, and the greater the bend. A slanting object partly out of water displays refraction. The object appears to bend at the interface of the air and water. Lenses refract light. Those that have concave, or hollowed-out, surfaces spread light rays apart. Those that have convex, or bulging, surfaces bring light rays closer together.

Chinese

I will be helping you with chinese compositions. The tips is to use good phrases. This is a example。
最难望的一天
  一个星期六下午，太阳高挂在天空中，像个大火球似的。妈妈爸爸俩帮我把家里装布了很漂亮因为经天是我的生日。朋友一到，我们就开始玩游戏。比如捉迷藏，跳绳，游泳。有些朋友说到：“慧君，你的父母装布得太漂亮！我很羡慕你有怎么好的父母。”我听到了，心里觉得很开心，妈妈爸爸付出很多我一定要感谢他们。最后，朋友们站在桌旁为我唱生日歌。所以，那天是我的最难忘的一天。爸爸妈妈是对我实在很好，我下定决心，从今天起要考好成绩，让父母心里安心。
Thank You