Passage 2
The top of the world is a wonderland. In winter, the temperature often falls to -30°F and the sun never rises. The ocean is surrounded by frozen ground. There are few people or trees, but to polar bears, the Arctic(北极)is home.
(78) Polar bears have thick fur, big paws and other features that make them well prepared for life in their tough environment. In fact, they need the Arctic sea ice for survival. But climate change is causing larger and larger areas of summer sea ice to melt(融化). Experts say that if warming patterns continue, the Arctic could be free of summer sea ice by 2050. That may cause two-thirds of the world’s 20,000 polar bears to be gone by then too.
Polar bears can’t survive for long on land. Seals are their main source of food. The only place where polar bears can hunt seals is on the ice. (79) Although these bears are strong swimmers, they are no match for lightning swift seals in the water. A polar bear has brilliantly clever strategies to overcome this disadvantage. In winter the bear waits motionless beside a seal’s breathing hole, which is a narrow tunnel through the ice. Often many hours pass before the seal comes up for air and the bear kills it with a powerful blow of its paw. In summer, the polar bears that live on land eat very little and wait for the sea ice to return.
With the sea ice forming later in the year and melting earlier, polar bears do not have enough opportunity to hunt and eat. Less sea ice makes it harder for the bears to catch the seals. The bears must swim longer distances between ice packs(大片浮冰), and they can’t always make it. The ice is also getting thinner. These conditions can cause polar-bear cabs to become separated from their mothers, who provide them with food.
Steven Amstrup is the chief scientist of Polar Bears International. The group aims to save the bears and their home. "The more people who see polar bears and understand their difficult situation, the better the chance we’ll alter our warming path in time to save them," he says.

Passage 3
Imagine a school that expected its students to become literate(有读写能力的) without any formal instruction. Most parents would be alarmed by such an approach, which would leave their children confused and with gaps in their understanding. This however has been the philosophy on character development in many of our schools. Why is the development of character seen as somehow different from the other skills that we teach
Of course there will always be learning by osmosis(耳濡目染)in any school, but as a teacher and primary school head I have found that a child’s moral literacy is strengthened when they acquire the building blocks of good character such as consideration, courage and honor: qualities which are commonly known as virtue(美德).
I personally find that exploring a virtue over a two-week period provides a simple and effective program that allows for the creative input of both teacher and student and a chance for the virtue to embed(使融入)itself. Once a lesson on a virtue such as honesty has been completed we need to allow time for children to practice this concept just as would be the case with fractions or verbs. Allowing children to role play a situation such as making up excuses to cover a mistake can be enormously interesting, and the drama can be frozen allowing the characters to be questioned about their feelings and motives. (80) It’s also a safe way for children to experience for themselves how a lie usually goes out of control.
Our role as educators is also to look for opportunities to help our students as they attempt to strengthen their characters. When something goes wrong we guide the young person to the virtue that will prevent it from happening again. For instance, when am student thoughtlessly disturbs the calm atmosphere of the library, instead of a response such as, "that was really disrespectful and selfish of you!" we draw out from them the required virtue: "When you’re walking through the library, what virtues do you need to use"

Passage 1
Is that 6 a.m. workout getting in the way of good sleep Don’t think your fat cells won’t notice. A new study published in The Annals of Internal Medicine (a medical journal) finds that inadequate shut-eye has a harmful effect on fat cells, reducing their ability to respond to insulin (胰岛素) by about 30 percent. Over the long-term, this decreased response could set the stage for type-2 diabetes (a medical condition in which someone has too much sugar in his or her blood), fatty liver disease and weight gain.
The study adds to a growing body of evidence that there’ “an intimate relationship between the amount of sleep we get and our ability to maintain a good, healthy body weight,” says sleep expert Helene Emsellem, director of the Center for Sleep and Wake Disorders in Chevy Chase, Maryland. (76) But Americans don’t seem to be getting the message that we need seven to nine hours par night. More than 1 in 5 of us, according to a report from the Centers for Disease Control and Prevention, is getting six or fewer hours of sleep per night, on average.
So how did researchers study fat cells in the Annals paper Matthew Brady of the University of Chicago and a group of colleagues selected and persuaded seven volunteers to take part in the research project. They were all young, thin and healthy and agreed to sleep for eight nights in a sleep lab. “For four nights they were allowed to stay in bed for 8.5 hours a night,” says Brady. Then, a month later, they came back for four additional nights——but this time they were allowed just 4.5 hours of sleep per night. And after each visit, researchers got a sample of their fat. (77) Brady explains that the fat cells responded significantly to the loss of sleep. “I was very surprised to be honest,” he says.
Bad things can happen when fat cells become less responsive to insulin. “Fat cells are actually your friend,” he says. “They’re there to store lipids (血脂).” When lipids stay inside the cells, your body can utilize the fat when you’re exercising or sleeping or going about your day. “However, when fat cells stare to become insulin resistant, the lipids star to leach out of the fat cells and rise in the bloodstream,” Brady says.

Passage 2
The top of the world is a wonderland. In winter, the temperature often falls to -30°F and the sun never rises. The ocean is surrounded by frozen ground. There are few people or trees, but to polar bears, the Arctic(北极)is home.
(78) Polar bears have thick fur, big paws and other features that make them well prepared for life in their tough environment. In fact, they need the Arctic sea ice for survival. But climate change is causing larger and larger areas of summer sea ice to melt(融化). Experts say that if warming patterns continue, the Arctic could be free of summer sea ice by 2050. That may cause two-thirds of the world’s 20,000 polar bears to be gone by then too.
Polar bears can’t survive for long on land. Seals are their main source of food. The only place where polar bears can hunt seals is on the ice. (79) Although these bears are strong swimmers, they are no match for lightning swift seals in the water. A polar bear has brilliantly clever strategies to overcome this disadvantage. In winter the bear waits motionless beside a seal’s breathing hole, which is a narrow tunnel through the ice. Often many hours pass before the seal comes up for air and the bear kills it with a powerful blow of its paw. In summer, the polar bears that live on land eat very little and wait for the sea ice to return.
With the sea ice forming later in the year and melting earlier, polar bears do not have enough opportunity to hunt and eat. Less sea ice makes it harder for the bears to catch the seals. The bears must swim longer distances between ice packs(大片浮冰), and they can’t always make it. The ice is also getting thinner. These conditions can cause polar-bear cabs to become separated from their mothers, who provide them with food.
Steven Amstrup is the chief scientist of Polar Bears International. The group aims to save the bears and their home. "The more people who see polar bears and understand their difficult situation, the better the chance we’ll alter our warming path in time to save them," he says.

Passage 1
Is that 6 a.m. workout getting in the way of good sleep Don’t think your fat cells won’t notice. A new study published in The Annals of Internal Medicine (a medical journal) finds that inadequate shut-eye has a harmful effect on fat cells, reducing their ability to respond to insulin (胰岛素) by about 30 percent. Over the long-term, this decreased response could set the stage for type-2 diabetes (a medical condition in which someone has too much sugar in his or her blood), fatty liver disease and weight gain.
The study adds to a growing body of evidence that there’ “an intimate relationship between the amount of sleep we get and our ability to maintain a good, healthy body weight,” says sleep expert Helene Emsellem, director of the Center for Sleep and Wake Disorders in Chevy Chase, Maryland. (76) But Americans don’t seem to be getting the message that we need seven to nine hours par night. More than 1 in 5 of us, according to a report from the Centers for Disease Control and Prevention, is getting six or fewer hours of sleep per night, on average.
So how did researchers study fat cells in the Annals paper Matthew Brady of the University of Chicago and a group of colleagues selected and persuaded seven volunteers to take part in the research project. They were all young, thin and healthy and agreed to sleep for eight nights in a sleep lab. “For four nights they were allowed to stay in bed for 8.5 hours a night,” says Brady. Then, a month later, they came back for four additional nights——but this time they were allowed just 4.5 hours of sleep per night. And after each visit, researchers got a sample of their fat. (77) Brady explains that the fat cells responded significantly to the loss of sleep. “I was very surprised to be honest,” he says.
Bad things can happen when fat cells become less responsive to insulin. “Fat cells are actually your friend,” he says. “They’re there to store lipids (血脂).” When lipids stay inside the cells, your body can utilize the fat when you’re exercising or sleeping or going about your day. “However, when fat cells stare to become insulin resistant, the lipids star to leach out of the fat cells and rise in the bloodstream,” Brady says.

Passage 1
Is that 6 a.m. workout getting in the way of good sleep Don’t think your fat cells won’t notice. A new study published in The Annals of Internal Medicine (a medical journal) finds that inadequate shut-eye has a harmful effect on fat cells, reducing their ability to respond to insulin (胰岛素) by about 30 percent. Over the long-term, this decreased response could set the stage for type-2 diabetes (a medical condition in which someone has too much sugar in his or her blood), fatty liver disease and weight gain.
The study adds to a growing body of evidence that there’ “an intimate relationship between the amount of sleep we get and our ability to maintain a good, healthy body weight,” says sleep expert Helene Emsellem, director of the Center for Sleep and Wake Disorders in Chevy Chase, Maryland. (76) But Americans don’t seem to be getting the message that we need seven to nine hours par night. More than 1 in 5 of us, according to a report from the Centers for Disease Control and Prevention, is getting six or fewer hours of sleep per night, on average.
So how did researchers study fat cells in the Annals paper Matthew Brady of the University of Chicago and a group of colleagues selected and persuaded seven volunteers to take part in the research project. They were all young, thin and healthy and agreed to sleep for eight nights in a sleep lab. “For four nights they were allowed to stay in bed for 8.5 hours a night,” says Brady. Then, a month later, they came back for four additional nights——but this time they were allowed just 4.5 hours of sleep per night. And after each visit, researchers got a sample of their fat. (77) Brady explains that the fat cells responded significantly to the loss of sleep. “I was very surprised to be honest,” he says.
Bad things can happen when fat cells become less responsive to insulin. “Fat cells are actually your friend,” he says. “They’re there to store lipids (血脂).” When lipids stay inside the cells, your body can utilize the fat when you’re exercising or sleeping or going about your day. “However, when fat cells stare to become insulin resistant, the lipids star to leach out of the fat cells and rise in the bloodstream,” Brady says.