题目内容
RS-232是DTE和DCE之间的接口标准，当作为DCE的MODEM和作为DTE的计算机相连时，按此标准需要连接的最少线数是 (37) 。MODEM收到呼叫信号后向计算机发送的信号是 (38) 。当数据发送完毕，计算机向MODEM发送的信号是清除 (39) ，MODEM随后向计算机发送清除 (40) 信号作为应答。当使用RS-232通信时，通常需要使用速率匹配功能，完成该功能的协议是 (41) 。
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The development of toothpaste began as long ago as 3000/5000 BC in the ancient countries of China and India. According to Chinese history, Huang-Ti claimed different types of pain felt in the mouth could be cured by sticking gold and silver needles into different parts of the jaw and gum. h was theories such as these that led to the development of dental cream. During the years 3000/5000 BC, Egyptians made toothpaste using a recipe of powdered ashes of hooves of oxen, myrrh, powdered and burned eggshells and pumice. It is assumed that the ancient Egyptians used their fingers to rub the mixture onto teeth.The tooth stick, the forerunner of the toothbrush, had not, as far as is known, been discovered at this time. From the records of the ancient countries of India, China and Egypt, it was the Greeks and Romans who developed and improved toothpaste and developed a leaden instrument for the extraction of teeth. They were also the first to bind loose teeth together and to support artificial teeth by means of gold wire. During 1000 AD, the Persians gave advice on the dangers of using hard toothpowders and recommendations were made to make toothpowder from burnt hartshorn, the burnt shells of snails and oysters and burned gypsum. Other Persian recipes included dried animal parts, herbs, honey and minerals. One formula for strengthening teeth included green lead, verdigris, incense, honey and powdered flint stone.Toothpowder or dentifrice was first available in Britain in the late 18th century. It came in a ceramic pot and was available either as a powder or paste. The rich applied it with brushes and the poor with their fingers. The powders were developed by doctors, dentists and chemists and often contained ingredients that were highly abrasive and harmful to the teeth, such as brick dust, china, earthenware or cuttlefish, and to make them more palatable, they contained glycerine. By the early nineteenth century, the ingredient stronchium was introduced, to strengthen teeth and reduce sensitivity, but it only really concentrated on the gums. In the late 18th century, borax powder was used to get the foaming effect. In 1873, an aromatic toothpaste in a jar was introduced in the U.S. and in 1896, Dental Cream was first packaged in collapsible tubes. Before the Second World War, the majority of toothpaste on the market used soap as an emulsifying agent, even though it was known that soap had certain inherent defects. What is the main subject of the passage（）。
The development of toothpaste began as long ago as 3000/5000 BC in the ancient countries of China and India. According to Chinese history, Huang-Ti claimed different types of pain felt in the mouth could be cured by sticking gold and silver needles into different parts of the jaw and gum. h was theories such as these that led to the development of dental cream. During the years 3000/5000 BC, Egyptians made toothpaste using a recipe of powdered ashes of hooves of oxen, myrrh, powdered and burned eggshells and pumice. It is assumed that the ancient Egyptians used their fingers to rub the mixture onto teeth.The tooth stick, the forerunner of the toothbrush, had not, as far as is known, been discovered at this time. From the records of the ancient countries of India, China and Egypt, it was the Greeks and Romans who developed and improved toothpaste and developed a leaden instrument for the extraction of teeth. They were also the first to bind loose teeth together and to support artificial teeth by means of gold wire. During 1000 AD, the Persians gave advice on the dangers of using hard toothpowders and recommendations were made to make toothpowder from burnt hartshorn, the burnt shells of snails and oysters and burned gypsum. Other Persian recipes included dried animal parts, herbs, honey and minerals. One formula for strengthening teeth included green lead, verdigris, incense, honey and powdered flint stone.Toothpowder or dentifrice was first available in Britain in the late 18th century. It came in a ceramic pot and was available either as a powder or paste. The rich applied it with brushes and the poor with their fingers. The powders were developed by doctors, dentists and chemists and often contained ingredients that were highly abrasive and harmful to the teeth, such as brick dust, china, earthenware or cuttlefish, and to make them more palatable, they contained glycerine. By the early nineteenth century, the ingredient stronchium was introduced, to strengthen teeth and reduce sensitivity, but it only really concentrated on the gums. In the late 18th century, borax powder was used to get the foaming effect. In 1873, an aromatic toothpaste in a jar was introduced in the U.S. and in 1896, Dental Cream was first packaged in collapsible tubes. Before the Second World War, the majority of toothpaste on the market used soap as an emulsifying agent, even though it was known that soap had certain inherent defects. According to the passage, stronchium was most useful for（）。
The old man stood there at a loss, his sunken eyes staring at the man seated behind the table. Raising his hand, he wiped the sweat from his forehead and heavily wrinkled face. He didn’t use the traditional kerchief and headband as usual, though he could feel the sweat running down his temple and neck, and he gave no reply to the man seated behind the table who went on asking him, "Why did you go in opening all the doors of the wards looking for your wife Why didn’t you come directly to Enquires" The old man kept silent. Why, though, was the man seated behind the table continuing to open one drawer after another His eyes busy watching him, he said, "I came here the day before yesterday wanting the hospital and looking for the mother of my children."The man seated behind the table muttered irritably, blaming himself for not having ever learned how to ask the right question, how to get a conversation going, and why it was that his question, full of explanations, and sometimes of annoyance, weren’t effective. He puffed at his cigarette as he enquired in exasperation, "What’ s your wife’ s name" The old man at once replied, "Zeinab Mohamed." The man seated behind the table began flipping through the pages of the thick ledger; each time he turned over a page there was a loud noise that was heard by everyone in the waiting room. He went on flipping through the pages of his ledger, pursing his lips listlessly, then nervously, as he kept bringing the ledger close to his face until finally he said, "Your wife came in here the day before yesterday" The old man in relief at once answered, "Yes, sir, when her heart came to a stop." Once again irritated, the man seated behind the table mumbled to himself, "Had her heart stopped she wouldn’t be here, neither would you." With his eyes still on the ledger, he said, "She’ s in Ward 4, but it’ s not permitted for you to enter her ward because there are other women there." Yawning, he called to the nurse leaning against the wall. She came forward, in her hand a paper cup from which she was drinking. Motioning with his head to the man, he said, "Ward Number 4 -Zeinab Mohamed." The nurse walked ahead, without raising her mouth from the cup. The old man asked himself how it was that this woman worked in a hospital that was crammed with men, even though she spoke Arabic. Having arrived at the ward, the nurse left him outside after telling him to wait; then, after a while, she came out and said to him, "There are two women called Zeinab Mohamed. One of them, though, has only one eye. Which one is your wife so that I can call her"The old man was thrown into confusion. One eye How am I to know He tried to recall what his wife Zeinab looked like, with her long gown and black headdress, the veil, and sometimes the black covering enveloping her face and sometimes removed and lying on her neck. He could picture her as she walked and sat, chewing a morsel and then taking it out of her mouth so as to place it in that of her first-born. Her children. One eye. How am 1 to know tie could picture her stretched out on the bed, her eyes closed. The old man was thrown into confusion and found himself saying, "When I call her, she’ll know my voice." The nurse doubted whether he was in fact visiting his wife; however, giving him another glance; she laughed at her suspicions and asked him, "How long have the two of you been married Again, he was confused as he said, ’ Allah knows best — thirty, forty years ...\ What does the title of the passage "The Unseeing Eye" suggest（）。
The Royal College of Nursing has warned that too many UK nurses are being lured to work in Australia. Last year almost 5,000 nurses formally signaled an intention to find work in Australian hospitals. Howard Catton, The RCN’s head of policy conceded nurses were receiving attractive offers, but said the UK still needed the nurses it was training. He said: "The Australians have stepped up their recruitment activity on the basis of what they believe is unemployment and downsizing in the UK." The Australian recruitment agencies that I’ve spoken to since I’ve been here are making very attractive offers. "It’s not just the starting salaries. The packages include air travel for nurses’ families as well--relocation expenses, temporary accommodation and the promise that they’ll support an application for permanent residency." A couple of employers even offer a "meet and greet" service at the airport with chauffeur-driven limousines, so the nurses are made to feel welcome as soon as their feet touch the ground."We still believe there are nursing shortages in the UK both in the NHS and the private sector." What is the main idea of the news item（）。
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