Making Light of¹ Sleep

　 All we have a clock located inside our brains. Similar to your bedside alarm clock， your internal clock² runs on a 24-hour cycle. This cycle，called a circadian rhythm，helps control when you wake，when you eat and when you sleep.
　　Somewhere around puberty，something happens in the timing of the biological clock. The clock pushes forward，so adolescents and teenagers are unable to fall asleep as early as they used to. When your mother tells you it"s time for bed，your body may be pushing you to stay up³ for several hours more. And the light coming from your computer screen or TV could be pushing you to stay up even later.
　　This shift⁴ is natural for teenagers. But staying up very late and sleeping late can get your body"s clock out of sync with the cycle of light and dark⁵. It can also make it hard to get out of bed in the morning and may bring other problems，too. Teenagers are put in a kind of a gray cloud⁶ when they don"t get enough sleep，says Mary Carskadon，a sleep researcher at Brown University in Providence，RI⁷ .It affects their mood and their ability to think and learn.
　　But just like your alarm clock，your internal clock can be reset. In fact，it automatically resets itself every day. How? By using the light it gets through your eyes.
　　Scientists have known for a long time that the light of day and the dark of night play important roles in setting our internal clocks. For years，researchers thought that the signals that synchronize the body"s clock⁸ were handled through the same pathways that we use to see.
　　But recent discoveries show that the human eye has two separate light-sensing systems. One system allows us to see. The second system tells our body whether it"s day or night.

词汇：

circadian/ sɜ:ˈkeɪdiən/ adj.  昼夜节奏的，生理节奏的

adolescent/ ˌædəˈlesnt/ n．青少年；adj．青少年的

puberty/ "pjʊ:bəti/ n．发育；青春期 

sync/siŋk/ n. （口语）同步；和谐，协调

synchronize/"siŋkrənaiz / V.（使）同时发生；（使）同步

注释：　　

1.make light of ：轻视，不在乎。例如： We should not make light of their achievements．我们不应当低估他们的成就。
2. your internal clock ：指的是第一句中的a clock located inside our brains ，也即是第二段第一句中的the biological clock （生物钟）。
3. stay up：不睡觉，熬夜
4. This shift：这种调整。指上文所描述的由于生理时间的变化青少年上床时间越来越晚的现象。
5. get your body"s clock out of sync with the cycle of light and dark ：打乱了你的生物钟与昼夜时间循环之间的平衡
6. gray cloud ：提不起精神的状态
7. Brown University in Providence， RI：位于美国罗得岛州普罗维登斯的布朗大学。RI是Rhode Island（罗得岛）的首字母缩写；Providence 是罗得岛州的首府。布朗大学是美国一流大学，创建于1764 年，是世界闻名的美国“常春藤联盟”（还包括哈佛大学、耶鲁大学、普林斯顿大学、布朗大学、哥伦比亚大学、宾夕法尼亚大学、达特茅斯大学和康奈尔大学）中的一员。
8. the signals that synchronize the body"s clock：平衡生物钟的光信号

According to the last two paragraphs， what did the previous researchers think about the human eye"s light-sensing system?

A:The human eye had two light-sensing systems. B:The human eye had one light-sensing system. C:The human eye could sense the light of day more quickly than the dark of night. D:The human eye could reset our internal clocks in accordance with the alarm clocks.

The project human resource management processes include the following:

A:Leadership, team building, and negotiatio B:Recruitment, labor relations, and personnel administratio C:Organizational structure planning, team buildin communication, and labor relation D:Human resource planning, acquire project team, develop project team, and manage project tea

human

(Human) society, (or in any) community, (may be spoken) (of as) a social organism.

A:Human B:or in any C:may be spoken D:of as

The discovery of a dwarfed (矮个的) "human being" who lived in Flores, Indonesia, up to 18,000 years ago is changing the way we think about the human family. This " Flores Human" was three foot tall and her brain was smaller than that of the average chimp (黑猩猩) ,yet she and her relatives apparently lived fully human lives. They seem to have made tools, worked together to find food and cook it, and perhaps even burried their dead with ceremony.
It was a major surprise to find tools associated with the new human family member. The tools are like those formerly seen only with European fossils (化石)from our own species; Homo sapiens (智人) ;and the oldest of them were made 9400 years ago. Homo sapiens is thought to have arrived in the island about 4000 years ago, much too late to be responsible for the tools. If this tiny human made the tools, then the inside structure (结构)of its brain must have been more like our own than a chimp’s, despite being just a third the size of ours.
This "new human" was suspected to be a dwarfed branch of Homo erectus (直立人). When creatures are separated in regions with rare resources but few enemies, being big is a disadvantage, and evolution tends to shrink them, a process known as island dwarfing, Could natural selection make a human smaller while keeping—even improving—mental ability Quite possibly, believes Christopher Wills of the University of California.
Has the "Flores Human" even shown the ability of language "I find it difficult to imagine that people could make tools, use fire, and kill large animals without fairly advanced communication," Wills says. Did "Flores Human" possess the basic components of human culture—such as the burying of the dead with ceremony Emiliano Bruner of the Italian Institute points out that Indonesia’s hot, wet environment is bad for fossilization. It is reasonable to assume, he says, that the 18,000-year-old bones of the most complete Flores woman were well-preserved because she was buried with special care.
This passage mainly talks about ______.

A:the tools made by "Flores Human" B:the language used by "Flores Human" C:the evolution of "Flores Human" D:the major surprising findings about "Flores Human"

The discovery of a dwarfed (矮个的) "human being" who lived in Flores, Indonesia, up to 18,000 years ago is changing the way we think about the human family. This " Flores Human" was three foot tall and her brain was smaller than that of the average chimp (黑猩猩) ,yet she and her relatives apparently lived fully human lives. They seem to have made tools, worked together to find food and cook it, and perhaps even burried their dead with ceremony.
It was a major surprise to find tools associated with the new human family member. The tools are like those formerly seen only with European fossils (化石)from our own species; Homo sapiens (智人) ;and the oldest of them were made 9400 years ago. Homo sapiens is thought to have arrived in the island about 4000 years ago, much too late to be responsible for the tools. If this tiny human made the tools, then the inside structure (结构)of its brain must have been more like our own than a chimp’s, despite being just a third the size of ours.
This "new human" was suspected to be a dwarfed branch of Homo erectus (直立人). When creatures are separated in regions with rare resources but few enemies, being big is a disadvantage, and evolution tends to shrink them, a process known as island dwarfing, Could natural selection make a human smaller while keeping—even improving—mental ability Quite possibly, believes Christopher Wills of the University of California.
Has the "Flores Human" even shown the ability of language "I find it difficult to imagine that people could make tools, use fire, and kill large animals without fairly advanced communication," Wills says. Did "Flores Human" possess the basic components of human culture—such as the burying of the dead with ceremony Emiliano Bruner of the Italian Institute points out that Indonesia’s hot, wet environment is bad for fossilization. It is reasonable to assume, he says, that the 18,000-year-old bones of the most complete Flores woman were well-preserved because she was buried with special care.

A:the tools made by "Flores Human" B:the language used by "Flores Human" C:the evolution of "Flores Human" D:the major surprising findings about "Flores Human"

What does the writer think about machines with human-like ability

A:He believes they will be useful to human beings. B:He believes that they will control us in the future. C:He is not quite sure in what way they may influence us. D:He doesn't consider the construction of such machines possible.