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某段铁路上有12个车站，共需要准备普通客票（）
分析：因为车票与两站的顺序有关，从甲站到乙站的车票不同于从乙站到甲站的车票，所以这个问题可以归结为排列问题来解．因为每一张车票对应着2个车站的一个排列，所以需要准备的车票种数，就是从12个车站中任取2个的排列数，即P122＝12×11＝132(种)．
答：C．
注意这是一道排列的直接应用题．在解这类题目时，首先要看能不能把问题归结为排列问题，也就是判断问题是否与排列顺序有关．如果与排列顺序有关，就可能归结为排列问题来解．其次分析在问题里，n个不同元素指的是什么，m个元素指的是什么，从n个元素中每次取出m个元素的每一个排列对应着问题里的什么事件．例如本题中从12个车站每次取出2个车站的一个排列就对应着一种车票．
学校将组织一次英语演讲比赛，打算邀请外教（John）来做评委。请你（Li Yuan）给他写一封e—mail，内容包括：?
·邀请他担任评委（judge）；?
·告知他比赛安排（如：时间、地点等）；?
·希望他赛后进行点评；?
·期待他能接受邀请。
A.I am free on Sunday.
B.See you then!
C.Where are you planning to go?
D.No,thanks.
E.I need a break!
F.Would you like to join us?
G.That is a lovely place.
H.When shall we leave?
Daniel:How are you doing,Linda?
Linda:To be honest,I am really tired of my
Heahh care experts have long drawn attention to the problems of eating too much sah．There isstrong evidence that a diet high in salt can lead to raised blood pressure．Since high blood pressure is amajor factor in heart disease．it makes sense to cut down on the salt people eat．?
In the past，food contained very little salt，and people added it to their food at the table．Very fewpeople ?add ?salt this ?way ?nowadays．However，the ?salt ?content ?of processed ?foods has ?gone ?updramatically．It’s now estimated that over three．quarters of the salt in the average diet comes fromprocessed foods，eaten without our being aware of it．?
Salt is added to food partly to extend shelf-life．but more often it’s dropped in to make up for theflavor lost in the manufacturing process．This is especially true of ready meals and highly processedfoods．but it’s also true of such basic food as biscuits，soups，and even bread．Much mass—producedbread，for instance．contains so much salt．half a gram for every hundred grams of bread--that it’sofficiallv classified bv the UK government as high——salt food．Salt has to be added to the bread becausefast Droduetion cuts down the time for the flavor to develop．Without added salt，the bread would tastelike paper．?
In the UK，the government has launched a campaign to cut down on the salt people eat．The UK Food Standards Agency argues that nearly half of the UK’s population eat too much salt—9．5 9 a day onaverage．Its aim is to bring down the average t0 69 a day．The idea is to cut the salt content in 85 keyfood categories such as bread．meat．and cakes．?
?What is the passage mainly about?
Heahh care experts have long drawn attention to the problems of eating too much sah．There isstrong evidence that a diet high in salt can lead to raised blood pressure．Since high blood pressure is amajor factor in heart disease．it makes sense to cut down on the salt people eat．?
In the past，food contained very little salt，and people added it to their food at the table．Very fewpeople ?add ?salt this ?way ?nowadays．However，the ?salt ?content ?of processed ?foods has ?gone ?updramatically．It’s now estimated that over three．quarters of the salt in the average diet comes fromprocessed foods，eaten without our being aware of it．?
Salt is added to food partly to extend shelf-life．but more often it’s dropped in to make up for theflavor lost in the manufacturing process．This is especially true of ready meals and highly processedfoods．but it’s also true of such basic food as biscuits，soups，and even bread．Much mass—producedbread，for instance．contains so much salt．half a gram for every hundred grams of bread--that it’sofficiallv classified bv the UK government as high——salt food．Salt has to be added to the bread becausefast Droduetion cuts down the time for the flavor to develop．Without added salt，the bread would tastelike paper．?
In the UK，the government has launched a campaign to cut down on the salt people eat．The UK Food Standards Agency argues that nearly half of the UK’s population eat too much salt—9．5 9 a day onaverage．Its aim is to bring down the average t0 69 a day．The idea is to cut the salt content in 85 keyfood categories such as bread．meat．and cakes．?
Which of the following is classified as high—salt food by the UK government?
Heahh care experts have long drawn attention to the problems of eating too much sah．There isstrong evidence that a diet high in salt can lead to raised blood pressure．Since high blood pressure is amajor factor in heart disease．it makes sense to cut down on the salt people eat．?
In the past，food contained very little salt，and people added it to their food at the table．Very fewpeople ?add ?salt this ?way ?nowadays．However，the ?salt ?content ?of processed ?foods has ?gone ?updramatically．It’s now estimated that over three．quarters of the salt in the average diet comes fromprocessed foods，eaten without our being aware of it．?
Salt is added to food partly to extend shelf-life．but more often it’s dropped in to make up for theflavor lost in the manufacturing process．This is especially true of ready meals and highly processedfoods．but it’s also true of such basic food as biscuits，soups，and even bread．Much mass—producedbread，for instance．contains so much salt．half a gram for every hundred grams of bread--that it’sofficiallv classified bv the UK government as high——salt food．Salt has to be added to the bread becausefast Droduetion cuts down the time for the flavor to develop．Without added salt，the bread would tastelike paper．?
In the UK，the government has launched a campaign to cut down on the salt people eat．The UK Food Standards Agency argues that nearly half of the UK’s population eat too much salt—9．5 9 a day onaverage．Its aim is to bring down the average t0 69 a day．The idea is to cut the salt content in 85 keyfood categories such as bread．meat．and cakes．?
What can be inferred about people’s use of salt in the past?
Heahh care experts have long drawn attention to the problems of eating too much sah．There isstrong evidence that a diet high in salt can lead to raised blood pressure．Since high blood pressure is amajor factor in heart disease．it makes sense to cut down on the salt people eat．?
In the past，food contained very little salt，and people added it to their food at the table．Very fewpeople ?add ?salt this ?way ?nowadays．However，the ?salt ?content ?of processed ?foods has ?gone ?updramatically．It’s now estimated that over three．quarters of the salt in the average diet comes fromprocessed foods，eaten without our being aware of it．?
Salt is added to food partly to extend shelf-life．but more often it’s dropped in to make up for theflavor lost in the manufacturing process．This is especially true of ready meals and highly processedfoods．but it’s also true of such basic food as biscuits，soups，and even bread．Much mass—producedbread，for instance．contains so much salt．half a gram for every hundred grams of bread--that it’sofficiallv classified bv the UK government as high——salt food．Salt has to be added to the bread becausefast Droduetion cuts down the time for the flavor to develop．Without added salt，the bread would tastelike paper．?
In the UK，the government has launched a campaign to cut down on the salt people eat．The UK Food Standards Agency argues that nearly half of the UK’s population eat too much salt—9．5 9 a day onaverage．Its aim is to bring down the average t0 69 a day．The idea is to cut the salt content in 85 keyfood categories such as bread．meat．and cakes．?
What is the main reason for reducing salt in food?
My boyfriend really enjoyed canoeing (划独木舟), and it took me a while to finally persuade himto take me on a canoe trip. Despite his great skill, he was nervous about my safety and described manyterrible situations that could happen. "They could also not happen," I said. I wanted to prove that I wastough and capable of adventuring.?
This would be a romantic adventure. We would row the canoe on the lake under a beautiful bluesky. I was confident it would all go according to plan.?
It did not go as planned. Instead,?it all went downhill. We hit a headwind (逆风). The flies werethe worst. An unknown animal outside our tent in the night forced us to get up twice to scare it away.We walked through knee-deep mud; we moved around so many fallen trees that we lost the wayfrequently. We had an unexpected thunderstorm on our second night. We hid in our tent from the bugs(虫子), too tired and bitten to even hold each other. When we were finally back in the car, my skinwas hot and angry with bug bites, I had barely slept in 72 hours and I had an injury on my forehead fromhitting it on the canoe.?
Yet I realized that I wanted to do it all again. Because I swam in a lake so warm it felt like asummer pool. ?I ate lunch on an island with the most beautiful pine trees. ?I' d also never beforeappreciated how thunder can make the ground tremble. I know why my boyfriend loves canoeing somuch. It' s for the challenge, the space, and the beauty of moving forward with your own two hands ina place of natural wonder. He didn' t say "I love you. " He said I was a good partner. I' ve foundsomething that I really like to do. That' s the more important thing.?
What would be the best title for the passage?
My boyfriend really enjoyed canoeing (划独木舟), and it took me a while to finally persuade himto take me on a canoe trip. Despite his great skill, he was nervous about my safety and described manyterrible situations that could happen. "They could also not happen," I said. I wanted to prove that I wastough and capable of adventuring.?
This would be a romantic adventure. We would row the canoe on the lake under a beautiful bluesky. I was confident it would all go according to plan.?
It did not go as planned. Instead,?it all went downhill. We hit a headwind (逆风). The flies werethe worst. An unknown animal outside our tent in the night forced us to get up twice to scare it away.We walked through knee-deep mud; we moved around so many fallen trees that we lost the wayfrequently. We had an unexpected thunderstorm on our second night. We hid in our tent from the bugs(虫子), too tired and bitten to even hold each other. When we were finally back in the car, my skinwas hot and angry with bug bites, I had barely slept in 72 hours and I had an injury on my forehead fromhitting it on the canoe.?
Yet I realized that I wanted to do it all again. Because I swam in a lake so warm it felt like asummer pool. ?I ate lunch on an island with the most beautiful pine trees. ?I' d also never beforeappreciated how thunder can make the ground tremble. I know why my boyfriend loves canoeing somuch. It' s for the challenge, the space, and the beauty of moving forward with your own two hands ina place of natural wonder. He didn' t say "I love you. " He said I was a good partner. I' ve foundsomething that I really like to do. That' s the more important thing.?
Which of the following happened during their canoe trip?
My boyfriend really enjoyed canoeing (划独木舟), and it took me a while to finally persuade himto take me on a canoe trip. Despite his great skill, he was nervous about my safety and described manyterrible situations that could happen. "They could also not happen," I said. I wanted to prove that I wastough and capable of adventuring.?
This would be a romantic adventure. We would row the canoe on the lake under a beautiful bluesky. I was confident it would all go according to plan.?
It did not go as planned. Instead,?it all went downhill. We hit a headwind (逆风). The flies werethe worst. An unknown animal outside our tent in the night forced us to get up twice to scare it away.We walked through knee-deep mud; we moved around so many fallen trees that we lost the wayfrequently. We had an unexpected thunderstorm on our second night. We hid in our tent from the bugs(虫子), too tired and bitten to even hold each other. When we were finally back in the car, my skinwas hot and angry with bug bites, I had barely slept in 72 hours and I had an injury on my forehead fromhitting it on the canoe.?
Yet I realized that I wanted to do it all again. Because I swam in a lake so warm it felt like asummer pool. ?I ate lunch on an island with the most beautiful pine trees. ?I' d also never beforeappreciated how thunder can make the ground tremble. I know why my boyfriend loves canoeing somuch. It' s for the challenge, the space, and the beauty of moving forward with your own two hands ina place of natural wonder. He didn' t say "I love you. " He said I was a good partner. I' ve foundsomething that I really like to do. That' s the more important thing.?
What does the sentence“it all went downhill”in Paragraph 3 mean?
My boyfriend really enjoyed canoeing (划独木舟), and it took me a while to finally persuade himto take me on a canoe trip. Despite his great skill, he was nervous about my safety and described manyterrible situations that could happen. "They could also not happen," I said. I wanted to prove that I wastough and capable of adventuring.?
This would be a romantic adventure. We would row the canoe on the lake under a beautiful bluesky. I was confident it would all go according to plan.?
It did not go as planned. Instead,?it all went downhill. We hit a headwind (逆风). The flies werethe worst. An unknown animal outside our tent in the night forced us to get up twice to scare it away.We walked through knee-deep mud; we moved around so many fallen trees that we lost the wayfrequently. We had an unexpected thunderstorm on our second night. We hid in our tent from the bugs(虫子), too tired and bitten to even hold each other. When we were finally back in the car, my skinwas hot and angry with bug bites, I had barely slept in 72 hours and I had an injury on my forehead fromhitting it on the canoe.?
Yet I realized that I wanted to do it all again. Because I swam in a lake so warm it felt like asummer pool. ?I ate lunch on an island with the most beautiful pine trees. ?I' d also never beforeappreciated how thunder can make the ground tremble. I know why my boyfriend loves canoeing somuch. It' s for the challenge, the space, and the beauty of moving forward with your own two hands ina place of natural wonder. He didn' t say "I love you. " He said I was a good partner. I' ve foundsomething that I really like to do. That' s the more important thing.?
Why did the writer want to have a canoe trip with her boyfriend?
