题目内容
Space is a dangerous place，not only because of meteors but also because of rays from the sun and other stars．The atmosphere again acts as our protective blanket on earth．Light gets through，and this is essential for plants to make the food which we eat．Heat，too，makes our environment endurable．Various kinds of rays come through the air from outer space，but enormous quantities of radiation：from the sun are screened off．As soon as men leave the atmosphere they are exposed to this radiation but their spacesuits or the walls of their spacecraft。if they are inside，do prevent a lot of radiation damage． Radiation is the greatest known danger to explorers in space．The unit of radiation is called “rem”．Scientists have reason to think that a man can put up with far more radiation than 0.1ream without being damaged；the figure of 60 reins has been agreed on．The trouble is that it isextremely difficult to be sure about radiation damage--a person may feel perfectly well，but theCells of his or her sex organs may be damaged，and this will not be discovered until the birth ofdeformed(畸形的)children or even grandchildren．Missions of the Apollo flights have had tocross belts of high radiation and，during the outward and return joumeys，the Apollo crew ac—cumulated a large amount of reams．So far，no dangerous amounts of radiation have been repor-ted，but the Apollo missions have been quite short．We simply do not know yet how men aregoing to get on when they spend weeks and months outside the protection of the atmosphere，working in a space laboratory．Drugs might help to decrease the damage done by radiation，butno really effective ones have been found so far． 根据以上内容，回答下列各题。 According to the first paragraph，the atmosphere is essential to man in that_________．
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Sequoyah was a young Cherokee Indian．son of a white trader and an Indian Squaw(北美印第安女人)．At an early age，he became fascinated by“tile talking leaf”，an expression thathe used to describe the white man’s written records．Although many believe this"talking leaf”to be a gift from tile Great Spirit，Sequoyah refused to accept that theory．Like other Indians oftile period，he was illiterate，but his determination to remedy tile situation led to the inventionof a unique 86 character alphabet based on the sound patterns that he heard． His family and friends thought him mad，but while recuperating(恢复)from a huntingaccident．he diligently and independently set out to create a form. of communication for his ownpeople as well as for other Indians．In l821，after twelve years of work，he had successfully de。veloped a written language that would enable thousands of Indians to read and write． Sequoyah’s desire to preserve words and events for later generation has caused him to be remembered among the important inventors．The giant redwood trees of-California，called“se-quoias(红杉)”in his honor，will further imprint his name in history． 根据以上内容，回答下列各题。 What is the most important reason that Sequoyah wiU be remeIll]bered？
When did the nalne “Air Jordan” becomewell known？
完成下列各题 通读下面的短文，掌握其大意。然后，从每小题的四个选项中选出可填入相应空白处的最佳选择，并把它前面的大写字母填入左边的括号里。 Sometimes I feel that being the mother of three small children is like operating a large cir- cus(马戏团)． 21________ afternoon last week，my three sons were playing peacefully in the back yard(院子)，22________the ball from one to another． I jumped at the chance to talk to one of my friends 23________ the phone，but before I 24________ to the phone，I could tell the boys had begun to quarrel with each other about something．I rushed out to 25 ________peace，but before I got there Charles had 26________ a rock at Mark，and hit him in the eye．By the time I got to the back yard，they had begun to 27 ________about this．Even David，the oldest boy，who won’t usually fight with anybody about 28________，was involved(卷入)．First，I 29________ them stop fighting，and then I examined Mark’s eye．I decided that it wasn’t going to develop into a black eye．But I felt that they should 30 ________ at least a little for 31________ they had done．“I'm going to 32________ to your father about this when he comes home tonight，”I said．“He and l will think of how to punish you．”Things were 33 ________ quiet after that for about half an hour，and then Charles 34 ________ a glass in the kitchen，and at almost the same 35________ ，Mark fell out of the apple tree． 21．
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