BOOK3unit4单元检测单

BOOK3---UNIT4 单元检测单语法填空：No one knows exactly how the earth began, as it happened so long ago. However, according to a widely _____(accept) theory,the universe began_____ a “Big Bang” that _____(throw) matter ____ all directions. After that,atoms began to form and combine to create stars and other _____(body)._____ several billion years after the “Big Bang”, the earth was still just a cloud of dust. _____ it was to become was uncertain until between 4.5 and 3.8 billion years ago when the dust settled into a solid globe. The earth became so_____( violence) that it was not clear whether the shape would last _____ not. It exploded _____( loud ) with fire and rock. They were in time ______( produce ) carbon, nitrogen, water vapor ____ other gases, _____ were to make the earth’s atmosphere. What is even ______( much )important is that as the earth cooled down, water began to appear on_____( it ) surface.Water had also appeared on other planets like Mars ____ unlike the earth, it _______( disappear ) later. _____ was not immediately obvious that water was to be fundamental to the ______( develop) of life. ______ many scientists believe is that the continued presence of water allowed the earth to dissolve ______(harm) gases and acids into the oceans and seas. This produced a chain reaction, which made ____ possible for life todevelop.Many millions of years later, the first extremely small plants began to appear on the surface of the water. They ______(multiply) and filled the oceans and seas with oxygen, _____ encouraged the later development of early shellfish and all sorts of fish. Next, green plants began to grow____ land. They ______( follow) in time by land animals. Some were insects. Others, _____ (call) amphibians, were able to live on land as well as in the water. Later when the plants _____ (grow) into forests, reptiles appeared ____ the first time. They produced young generally by ____( lay ) eggs. After that, some huge animals, ____(call ) dinosaurs, developed. They _____ (lay ) eggs too and existed on the earth for more than 140 million years.However, 65 million years ago the age of the dinosaurs ended. ____ they suddenly disappeared still remains a mystery. This ________ ( disappear ) made possible the rise of mammals on the earth. These animals were different ____ all life forms in the past, because they gave birth _____ young baby animals and produced milk to feed them.Finally about 2.6 million years ago some small clever animals, now with hands and feet, appeared and spread all over the earth. Thus they have, _____ their turn, become ____ most important animals on the planet. But they are not _____(look ) after the earth very well. They are _____(put ) too much carbon dioxide into the atmosphere, which prevents heat _____escaping from the earth into space. _____ a result of this, many scientists believe the earth may become too hot to live ____. So _____ life will continue on the earth for millions of years to come will depend _____ whether this problem can be solved.翻译：1，在宇宙大爆炸的数百万年后,地球只是一团尘埃.它真正形成大约是在45亿至38亿年前,那时尘埃逐渐聚拢成为一个固体星球.但是这时的地球很不稳定,不知它的形状是否还会维持.地球上发生爆炸,迸发出火焰和岩石.它们立即产生碳、氮气、水蒸气和其他气体,这就是将来形成大气层的主要元素.更重要的是,当地球的温度逐渐下降时,水蒸气开始冷凝附着在地球的表面.2，水同样也出现在其他的星球上,比如说火星.但与地球不同,它在后来便消失了.水是不是生命的产生的基础,这点仍然不是很清晰.很多科学家认为,水的持续产生使得地球上的有害气体和酸性物质进入海洋.这引起了一系列的反应,这些反应同样保证了生命的产生.3，有些是昆虫.其它的是两栖动物,它们可以在陆地和水中生存.4，究竟恐龙为何会突然消失仍然是个迷.5，最后在260万年前出现了一些小型的智能动物,现在有手和脚,并在地球上各处出现并行遍地球.它们因此一跃成为了地球上最重要的动物.但是它们漠不关心地球.它们将二氧化碳排向大气中,使得热无法从地球上有效的散失.因此,许多科学家认为地球会变得过热而无法生存.因而接下来的数百万年中是否仍然有生命存在于这个星球仍就尚未解决.改错：Last month I was luck enough to have a chance to make a trip into space with my friend Li Yanping, a astronomer. We visited the moon by our spaceship!Before we left, Li Yanping explained me that the force of gravity would change three times in our journey and that the first change would be most powerful. Then we were off. As the rocket rised into the air, we were pushed back into our seats because we were trying to escape the pull of the earth gravity. It was so hard that we could not say anything to each other. Gradually the weigh lessened and I was able to talk to him. “Why is the spaceship not fall back to the earth? On the earth if I fell from a tree I will fall to the ground.” I asked. “We are too far from the earth now tofeel it’s pull,” he explained, “so we feel as if no gravity at all. When we get close to the moon, we shall feel its gravity pulling us, and it will not be as strong a pull as the earth.” I cheered up immediate ly and floated weightless around in our spaceship cabin watch the earth become smaller and the moon larger.When we ge t there, I wanted to explore immediately. “Come on,” I said. “If you are right, my weight will be l ittle than on the earth because the moon is smaller and I will be able to move more free. I might even grow tall if I stay here long enough. I shall certainly weigh less!” I laughed but climbed down the steps from the spaceship. But when I try to step forward. I found I was carrying twice as far as on the earth and fall over. “Oh dear,” I cried, “walk does need a bit of practice now that gravity has changed.” After a while I got hang of it and we began to enjoy us. Leaving the moon’s gravity was not as painful as leave the earth’s. But returning to the earth was very frightened. We watched, amazing as fire broke out on the outside of the spaceship as the earth gravity increased. Again we were pushed hard into ours seats as we came back to land. “That was very exhausting and very exciting too,” I said. “Now I know very more about gravity! Do you think we could visit some stars next times?” “Of course,” he smile, “which star would you like to go to?”。