1.We talk about energy all the time-"Zilch,the energy food," "energy crisis," and so on.If asked to define it,however,we'd probably respond with something like "Well,it's-uh-well,you know-electricity."
1、我们时时刻刻讨论着能：“能量食物”，“能源危机”，等等。如果要我们去给能下个定义，答案很可能是一些模棱两可的话：“哦，能量是，嗯，你知道，电。”
2.True;electricity is one kind of energy.However,energy comes in many forms.You cannot see or smell or taste energy,but it's always there,and one of the most fascinating things about it is its ability to change from one form to another-like magic.This principle of change is what keeps everything-and everyone-going in this world of ours.
2、确实，电是能量中的一种。但是，能量可以来自多种形式。你看不见、闻不到、也品尝不了能，但是，它始终存在着，关于能量，最吸引人的就是，它具有从一种形式转换成另外一种形式的能力，简直如同魔术。这些转化的原理是维持我们这个世界每一样事物、每一个人的运动。
Heat Energy
热能
3.When a fuel unites with oxygen,we say the fuel burns; what is really happening is that chemical energy(fuel and oxygen) is changing to heat energy.When the fuel(food) we eat unites with the oxygen we breathe,we then have heat energy to run our bodies.
3、当燃料与氧气结合，我们就说燃料开始燃烧了，实际发生的是化学能（燃料与氧气）转化成热能。当燃料（我们吃的食物）与我们呼吸的氧气结合，我们获得我们身体运动所需的热能。
4.When you pop a frozen waffle into the toaster,electrical energy turns into heat energy.
4、当你取出一块冷冻饼放进烤面包器时，电能转化成了热能。
5.In the internal-combustion engine of a car,an electric spark explodes gasses in the cylinder;the heat energy moves the pistons,becoming mechanical energy to move the car.
5、在汽车的内燃机引擎里，电火花引爆气缸里的燃料气体，然后热能推动活塞，成为机械能推动汽车行驶。
6.In a steam engine,the chemical energy of fuel is changed to heat energy;the heated water,now steam,forces the pistons to move.In a steam turbine,the steam pushes against blades.In both cases,mechanical energy results.
6、在蒸汽机里，燃料里的化学能转化成热能，加热水，成为水蒸汽，推动活塞运动。在燃气轮机里，水蒸汽推动的是叶片。在这两种情况中，都是机械能起的作用。
7.This changing from one form of energy to another can continue almost indefinitely.If,for instance,the steam engine or turbine is connected to a generator,the mechanical energy can become electrical energy,which can become heat energy(for the electric stove),mechanical energy(for the washer),etc.
7、能量从一种形式转化为另一种形式的变化几乎能够平稳连续进行。比如说，如果蒸汽机或者蒸汽轮机和一个发电机联接起来，那么机械能就可以转化成电能，然后转化成热能（比如电炉）、机械能（如洗衣机）等等。
8.Thus,energy readily changes back and forth from one form to another.What starts out as one form of energy may be a totally different form when it reaches its final use.
8、因此，能量可以轻易地从一种形式到另一种形式来回转换。从最初的能量形式到最后的使用形式，能的形态可能已经完全改变了。