三年级年级英语作文第8单元
三年级年级英语作文第8单元
学习啦在线学习网 英语作文的写作对于小学生而言有一定的难度,你知道三年级八单元的英语作文要怎么写吗?下面是学习啦小编给大家精心挑选的三年级年级英语作文第8单元,希望大家喜欢!供你参考和阅读!
三年级年级英语作文篇1
学习啦在线学习网 The Source of EnergyA summary of the physical and chemical nature of life must begin, not on the Earth, but in the Sun; in fact, at the Sun's very center. It is here that is to be found the source of the energy that the Sun constantly pours out into space as light and heat.
学习啦在线学习网 This energy is liberated at the center of the Sun as billions upon billions of nuclei of hydrogen atoms collide with each other and fuse together to form nuclei of helium, and in doing so, release some of the energy that is stored in the nuclei of atoms. The output of light and heat of the Sun requires that some 600 million tons of hydrogen be converted into helium in the Sun every second. This the Sun has been doing for several thousands of millions of years.The nuclear energy is released at the Sun's center as high-energy gamma radiation, a form of electromagnetic radiation like light and radio waves, only of very much shorter wavelength. This gamma radiation is absorbed by atoms inside the Sun to be reemitted at slightly longer wavelengths.This radiation, in its turn is absorbed and reemitted. As the energy filters through the layers of the solar interior, it passes through the X-ray part of the spectrum eventually becoming light.
学习啦在线学习网 At this stage, it has reached what we call the solar surface, and can escape into space without being absorbed further by solar atoms. A very small fraction of the Sun's light and heat is emitted in such directions that after passing unhindered through interplanetary space, it hits the Earth.
生命的物理和化学性质的摘要必须开始,不是地球上的,但在阳光下;事实上,在太阳的中心。在这里找到太阳的能量的来源不断吐出以光和热的形式进入太空。
这种能量是解放的中心太阳几十亿氢原子的原子核相互碰撞和融合在一起形成氦核,并在这一过程中,释放的能量存储在原子的原子核。太阳的光和热的输出要求6亿吨氢转化为氦太阳每秒钟。这太阳已经做了几千几百万年。核能在太阳的中心被释放为高能的伽马辐射,电磁辐射的一种形式,就象光波和无线电波,只是波长要短得多。这种伽玛射线被太阳内的原子所吸收,然后重新释放为波长稍长一些的光波。这种辐射,而后释放吸收。随着能源太阳内部一层层渗透出来的过程中,它经过了光谱中x射线部分,最后变成了光。
学习啦在线学习网 在这个阶段,它已经到达我们所称的太阳表层,并且可以逃到空间而不再被太阳原子所吸收。只有很小一部分太阳的光和热由此方向释放出来,并且未被阻挡,不受阻碍地通过星际空间后,撞上了地球。
三年级年级英语作文篇2
学习啦在线学习网 Hello! My name is Chen Danqing. My English name is Joy. I'm 14 years old. I'm a happy girl. I have a happy family. My father and my mother are both office workers. They're busy. But at weekends, they always cook nice food for me. I'm happy in the family. I love my parents and they love me very much.
学习啦在线学习网 I'm a student at Dongzhou Middle School. It is very big and beautiful. There are many classroom buildings and office buildings. Besides the buildings, there is a big playground. After school, there are lots of boys playing basketball on it. I think they are happy. There are a lot of flowers and trees in my school. They are beautiful. I like my school. In my school, I have many friends. All my friends are polite and helpful. My friends are all nice to me. They can make me happy. So I like playing with them.
My hobbies are listening to music and reading. I like pop music very much. I dislike sports because I'm not strong. It's hard for me.
学习啦在线学习网 I have a happy family, a beautiful school and many nice friends. I enjoy every day.
三年级年级英语作文篇3
My First Day on the Campus
学习啦在线学习网 I still remember the day when I first came to the college. Being a boy of 17, I was longing for a new life as a college student; but, at the same time, I had no idea what college life would be like.
学习啦在线学习网 That morning when the bus carried me to the gate of the college. I was so excited that my heart was beating very fast as if it would leap out of my mouth. From now on, I would be a student of this college. After registration, we were led by an instructor to the dormitory, where, for the first time, we were going to live without parents but roommates. I was so clumsy that I did not know how to make the bed and fix the mosquito net.
In the afternoon, I took a walk around the campus together with my roommates. To think of studying in such a beautiful place made me feel quite proud of myself. As we were walking along, talking and laughing, a voice came into our ears, "Oh, look at these freshmen!" It was our middle-school-students' looking that gave us away. We continued our tour of the college, inspecting every building and every garden until the sun began to set.
学习啦在线学习网 In the evening, we sat together, talking about the past and the future. We were so excited that no one wanted to go to bed.
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