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Why don’t birds get lost on their long flights from one place to another Scientists have puzzled over this question for many years. Now they’re beginning to fill in the blanks.Not long ago, experiments showed that birds rely on the sun to guide them during daylight hours. But what about birds that fly by night Tests with artificial stars have proved that certain night - flying birds are able to follow the stars in their long- distance flights.A dove (鸽子)had spent its lifetime in a cage and had never flown under a natural sky. Yet it showed an inborn ability to use the stars for guidance. The bird’s cage was placed under an artificial star-filled sky. The bird tried to fly in the same direction as that taken by his outdoor cousins. Any change in the position of the artificial stars caused a change in the direction of his flight.But the stars are apparently their principal means of navigation(航行)only. When the stars are hidden by clouds, they seemingly find their way by such landmarks as mountain ranges, coast lines, and river courses. But when it’s too dark to see these, the doves circle helplessly, unable to find their way. The experiment with the dove implied that ().
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有关德育外延的界定应当遵循“守一而望多”的原则,“守一”即是强调_____作为德育范畴的最基本的内涵；“望多”是指德育还应包括_____、_____等项基本价值教育的内涵。
阅读下面短文，回答下面问题。 父亲喜欢兰草，过些日子，就要到深山中一趟，带回些野兰来培栽。几年问，家里庭院就有了百十余品种，像要做一个兰草园圃似的。方圆十几里的人就都跑来观赏，父亲并不因此而得意，反而有几分愠怒。以后又进山去、可不再带回那些野生野长的兰草了。这事使我很奇怪，问他，又不肯说，只是有一次再进山的时候，要我和他一块去访兰。 我们走了半天，一直到了山的深处。那里有一道瀑布，从几十丈高的山崖直直垂下，老远就听到了轰轰隆隆的响声，水沫扬起来，弥漫了半个天空，日光在上面浮着，晕出七彩迷丽的虚幻。我们沿谷底走，便看见有很多野兰草，盈尺高的，都开了淡淡的兰花，像就地铺着一层寒烟；香气浓烈极了，气浪一冲，站在峡谷的任何地方都闻到了。 我从未见过这么清妙的兰草，连声叫好，要动手挖。父亲却把我制止了，问道：“你觉得这里的兰草好呢，还是家里的那些好呢” 我说：“这里的好!” “怎么好呢” 我却说不出来。“好像是味儿不同吗” “是的。” “这是为什么一样的兰草，长在两个地方就有两个味儿” 父亲说：“兰草是空谷的幽物，得的是天地自然的原气。长的是山野水畔的趣姿；一经培栽，便成了玩赏的盆景。” “但它确实叶更嫩、花更繁更大了呢!” “样子似乎是美了，但美得太甜、大媚，格调也就俗了。” 父亲的话是对的，但我不禁惋惜：这么精神的野兰在这么个空谷僻野，叶是为谁长的，花是为谁开的，会有几个人欣赏它呢 “这正是它的不俗处。它不为被人欣赏而生长，却为着自己的特色而存在着，所以它才长得叶纯，开得花纯，楚楚的有着它的灵性。” 父亲拉我坐在潭边。他看着兰，也在看着我，说；“做人也是这样啊，孩子!人活在世上，不能失了自己的真性，献媚处事，就像盆景中的兰草一样降了品格；低俗的人不会对社会有贡献的。” 我深深地记着父亲的话。从那以后，已经是15年过去了，我一直未敢忘却过。 (贾平凹《访兰》) 文中“父亲”生气的原因是：
Life really should be one long journey of joy for children born with a world of wealth at their feet.Internationally famous child doctor Robert Coles is the world’s top expert on the influence of money on children. He has written a well-known book on the subject, The Privileged Ones, and his research shows that too much money in the family can cause as many problems as too little. "Obviously there are certain advantages to being rich," says the 53-year-old doctor, "such as better health, education and future work prospects. But most important is the quality of family life. Money can’ t buy love. "It can buy a lot of other things, however, and that’s where the trouble starts. Rich kids have so much to choose from that they often become confused. Over-indulgence (娇惯) by their parents can make them spoilt. They tend to travel more than other children, from home to home and country to country, which causes feelings of restlessness."But privileged children do have a better sense of their positions in the world," adds Mr. Coles, "and they are more self-assured. The rich children inherit the property from their parents and enjoy a high income. So money will never be one of their problems. However, they will have a sense of isolation," warns Dr Coles, " and they could suffer from the hardship of not being able to deal with the everyday world because they will never really be given the chance. Everything they have achieved is because of an accident of birth. There can be no tremendous inner satisfaction about that. "Today’s wealthy parents perhaps realize their riches can be more of a heavy load than a happiness to their children. So the first thing for them to consider is to ensure that their families are as rich in love as they are in money. In his book The Privileged Ones, Dr Coles implies that ().
Questions 14-16 are based on the following passage. You now have 15 seconds to read Questions 14-16. When did Abraham Lincoln announce an order to free the slaves
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