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Passage One

Although no one is certain why migration occurs, there are several theories. One theory claims that prehistoric birds of the Northern Hemisphere were forced south during the Ice Age. As the glaciers melted, the birds came back to their homelands, spent the summer, and then went south again as the ice advanced in winter. In time, the migration became a habit in spite of the disappearance of glaciers. Another theory proposes that the ancestral home of all modern birds was the tropics. When the region became overpopulated, many species were crowded north. During the summer, there was plenty of food, but during the winter, scarcity forced them to return to the tropics. A more recent theory suggests a relationship between increasing daylight and the stimulation of certain glands(腺)in the birds’ bodies that may prepare them fo A. exact reasons for migration are not known B. birds migrate because of changes in temperature C. the ancestral home of all birds was the tropics D. glaciers caused birds to migrate 查看答案 更多"Passage One Although no o"的相关试题: [单项选择] Passage One Although no one is certain why migration occurs, there are several theories. One theory claims that prehistoric birds of the Northern Hemisphere were forced south during the Ice Age. As the glaciers melted, the birds came back to their homelands, spent the summer, and then went south again as the ice advanced in winter. In time, the migration became a habit in spite of the disappearance of glaciers. Another theory proposes that the ancestral home of all modern birds was the tropics. When the region became overpopulated, many species were crowded north. During the summer, there was plenty of food, but during the winter, scarcity forced them to return to the tropics. A more recent theory suggests a relationship between increasing daylight and the stimulation of certain glands(腺)in the birds’ bodies that may prepare them fo A. stopped migrating B. continued migrating C. stayed in the north D. migrated south and stayed there 查看答案 [单项选择]Passage Five Although no one is Certain why migration occurs, there are several theories. One theory is based upon the premise that prehistoric birds of the northen Hemisphere were forced south during the Ice Age, when glaciers covered large parts of Europe, Asia, and North America. As the glaciers melted, the birds came back to their homelands, spent the summer, and then went south again as the ice advanced in winter In time, the migration became a habit, and now, although the glaciers have disappeared, the habit continues. Another theory proposes that the ancestral home of all modern birds was the tropics. When the region became overpopulated, many species were crowded north. During the summer, there was plenty of food, but during the winter, scarcity forced them to return to the tropics. A more recent theory, known as photoperiodism, A. stopped migrating B. continued migrating C. began migrating again D. migrated south and stay there 查看答案 [单项选择]Passage One Although speech and writing are the special means of communicating of humans, the interchange also takes place in many other ways. A person may relay his or her feelings, thoughts, and reactions through body positioning, body contact, body odors, eye contact, responsive actions, habits, attitudes, interests, state of health, dress and grooming, choice of life-style, and use of talents --- in fact, through everything the individual says or does. In turn, every person is constantly receiving multitudes of external and internal messages through his or her five senses and personal biorhythm system. An individual screens, selects, regulates, and controls specific aspects of this Information through a process of mental choices. Some of these choices are automatic; some are subconscious because of habit, block, or lack of development; and some are made by a conscious process. The degree to which a person is able to communicate depends upon the extent of his or her cons A. is characterized by two features, form and meaning B. is mainly conducted through speech and writing C. is of two functions, stimulation and response D. takes two forms, verbal and nonverbal 查看答案 [单项选择] Passage One Historically, although the children of immigrants may have grown up bilingual and bicultural, many did not pass on much of their parents’ language or culture to their own children. Thus, many grandchildren of immigrants do not speak the language of the old country and are "American" by culture. However, in some parts of the country with established communities that share a common language or culture, bilingualism and biculturalism continue. This is particularly true in communities where new immigrants are still arriving. In general, cultural pluralism (多元化) is more accepted in the United States today than it was in the first half of the 20th century, and many of the school systems have developed bilingual programs and multicultural curricula. At the close of the 20th century, there seemed to be a rise i A. don’t like their old language and culture B. don’t speak English and reject American culture C. only speak English and are "American" by culture D. only live in established communities where new immigrants are still arriving 查看答案 [单项选择] Passage One One of the most interesting experiments in electronic communication I’ve ever seen is coming from Wave. It’s real-time e-mail. What that means is that as you’re typing a message in Wave, either a new message or a reply, the person you’re writing to can see what you’re typing as you type it. Sounds awful, right You don’t have to use Wave in this real-time way. It also works as a standard e-mail. What’s really different about Wave is that if you’re replying to a message and the person you’re replying to happen to be online, they can jump into the conversation at that point, and change what is an e-mail conversation into an instant message conversation or a chat. Wave right now is still closed to most users. And Wave isn’t yet connected to other communication systems, like regular e-mail, which means that the only people we can Wave with are other people on Wave as well. So we don’t yet know what using Wave will be like A. Optimistic. B. Indifferent. C. Pessimistic. D. Critical. 查看答案 我来回答: 提交 最新试题 ●    水平接地网埋深应符合设计要求，当设计无规定时，不宜小于（）m。 ●    据有关媒体报道，在我国，排污权交易的第一个典型案例出现在江苏省。2002年夏，江苏省太仓市计划扩建太 ●    人在后天习得的行为都具有（） ●    什么是科学发展观的核心内容，也是构建社会主义和谐社会的根本前提？ ●    简述缔约能力的法律适用。 ●    对付避税地的法规首先是由（）在20世纪60年代初率先制定的。 网站地图 我要搜题网  版权所有  ©2023  湘ICP备18016427号   购买搜题卡查看答案 [会员特权] 开通VIP， 查看 全部题目答案 [会员特权] 享免全部广告特权 推荐91天 ¥36.8 ￥80元 31天 ¥20.8 ￥40元 365天 ¥88.8 ￥188元 请选择支付方式 微信支付 支付宝支付 点击支付即表示同意并接受了《购买须知》 立即支付 系统将自动为您注册账号 已有账号登录 找回账号密码 请使用微信扫码支付 订单号： 请不要关闭本页面，支付完成后请点击【支付完成】按钮 支付完成 取消支付 恭喜您，购买搜题卡成功 系统为您生成的账号密码如下： 账号 密码 重要提示：请拍照或截图保存账号密码！ 我要搜题网官网：https://www.woyaosouti.com 我已记住账号密码