[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. there was not enough food there in the winter B. there were too many birds C. there were too many glaciers D. there was too much daylight 查看答案 更多"Passage Five Although no "的相关试题: [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 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 One of the most strikingly apparent instances of extrasensory perception is the precognitive experience, when a person has a compelling perception of a coming disaster, news of death of a loved one, or a communication from a long-lost friend, and the predicted event then happens. Many who have had such experiences report that the emotional intensity of the precognition and its subsequent verification provide an overpowering sense of contact with another realm of reality. I have had such an experience myself. Many years ago, I awoke in the middle of night in a cold sweat, with a certain knowledge that a close relative had suddenly died. I was so gripped with the haunting intensity of the experience that I was afraid to place a long-distance phone call, (for fear that the relative would trip over the telephone cord or something and m A. some kind of disaster a person experienced in his childhood B. a vague sense that something will happen and it does happen later C. the prediction of the death of a close friend D. uncertainty about an impending accident 查看答案 [单项选择]Passage Five One of Dara Torres’ trainers is walking all over me. Literally. I’m lying on my stomach as Steve Sierra concentrates his entire 160 lb. on my glutei and hamstrings. It hurts, but in a good way. It’s all part of the flexibility--and strength-building regimen that Torres, who is making history, as the oldest swimmer to compete in the Olympics, credits with getting her 41-year-old body in good-enough shape to race athletes half her age. But resistance stretching, as it is called, is not just for the Olympians among us. Its focus on maximizing muscle flexibility has been useful for everyone from injured NBA players to children with cerebral palsy. The exercises may not look like much--they generally require no equipment other than a mat and maybe a towel and some straps--and they may not feel that strenuous, but you know the next day that you’ve had a workout. Resistance stretching centers on flexing your muscles even as you stretch them; for example, inst A. live longer B. look attractive C. physically active D. rid of disease 查看答案 我来回答: 提交 最新试题 ●    [判断题]压接钳的出力主要取决于压接模具的宽度。 ●    进行泌尿系统检查时，需要做碘过敏试验的是（）。 ●    [单选题]相对股票投资而言，企业进行债券投资的优点是（　　）。 ●    [单选题]教育部发布了《教育部关于×××计划的报告》，下列说法错误的是()。 ●    [单选题]下列商业银行业务中，不属于借款业务的是（ ）。 ●    [单选题]杀菌效果最好的乙醇浓度是: ( 网站地图 我要搜题网  版权所有  ©2024  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： 截图扫码使用小程序[完全免费查看答案] 前往小程序 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