3 . Being stuck at home doesn’t mean that learning stops. In fact, it's just the opposite. Here are some activities and resources to foster (促进) kids' imagination and build their curiosity at home.

Let's Get down to Science

The science lab at school may be closed, but kids can still put on goggles and a white lab coat and learn at home. This Test Tube Experiment Kit will make them feel like a genius in no time. Kids will get the chance to learn about basic chemistry, physics, and more by creating pop-resistant bubbles, bouncy balls, and other objects.

To Infinity (无穷) and Beyond

Earth is a part of the Milky Way, but do kids know how many galaxies there are in the universe? There are so many fun and fascinating things to learn about space that the possibilities truly go to infinity and beyond. A great way to start your child's educational space adventure is with this Discovery Real Life Sticker and Activity Book: Space.

Take a Walk on the Wild Side

Biology class is in session! Here's kids' chance to get up close and personal with a great white shark without putting on a wetsuit. This 4D Great White Shark Anatomy Kit allows them to get an inside look at what makes these predators of the deep so powerful. And then take an even deeper dive into a shark's world with I'm a Shark.

Let your kid take advantage of this time at home and find new ways to keep exploring the world around him.

1. What is common among these activities above?

A．They are all performed outdoors.

B．They are all associated with physics.

C．They all recommend some resources for kids to study.

D．They are all carried out by the way of experimenting.

2. Which resource favors children interested in stars?

A．The Test Tube Experiment Kit.

B．Discovery Real Life Sticker and Activity Book: Space.

C．The 4D Great White Shark Anatomy Kit.

D．I'm a Shark.

3. What's the shared goal of the activities?

A．To gain financial benefits.	B．To save kids from boredom.
C．To explore new technologies.	D．To inspire kids to study at home.

4 . For those who can stomach it, working out before breakfast may be more beneficial for health than eating first, according to a study of meal timing and physical activity.

Athletes and scientists have long known that meal timing affects performance. However, far less has been known about how meal timing and exercise might affect general health.

To find out, British scientists conducted a study. They first found 10 overweight and inactive but otherwise healthy young men, whose lifestyles are, for better and worse, representative of those of most of us. They tested the men’s fitness and resting metabolic (新陈代谢的) rates and took samples (样品) of their blood and fat tissue.

Then, on two separate morning visits to the scientists’ lab, each man walked for an hour at an average speed that, in theory, should allow his body to rely mainly on fat for fuel. Before one of these workouts, the men skipped breakfast, meaning that they exercised on a completely empty stomach after a long overnight fast (禁食). On the other occasion, they ate a rich morning meal about two hours before they started walking.

Just before and an hour after each workout, the scientists took additional samples of the men’s blood and fat tissue.

Then they compared the samples. There were considerable differences. Most obviously, the men displayed lower blood sugar levels at the start of their workouts when they had skipped breakfast than when they had eaten. As a result, they burned more fat during walks on an empty stomach than when they had eaten first. On the other hand, they burned slightly more calories (卡路里), on average, during the workout after breakfast than after fasting.

But it was the effects deep within the fat cells that may have been the most significant, the researchers found. Multiple genes behaved differently, depending on whether someone had eaten or not before walking. Many of these genes produce proteins (蛋白质) that can improve blood sugar regulation and insulin (胰岛素) levels throughout the body and so are associated with improved metabolic health. These genes were much more active when the men had fasted before exercise than when they had breakfasted.

The implication of these results is that to gain the greatest health benefits from exercise, it may be wise to skip eating first.

1. The underlined expression “stomach it” in Paragraph 1 most probably means “______”.

A．digest the meal easily	B．manage without breakfast
C．decide wisely what to eat	D．eat whatever is offered

2. Why were the 10 people chosen for the experiment?

A．Their lifestyles were typical of ordinary people.

B．Their lack of exercise led to overweight.

C．They could walk at an average speed.

D．They had slow metabolic rates.

3. What happened to those who ate breakfast before exercise?

A．They successfully lost weight.	B．They consumed a bit more calories.
C．They burned more fat on average.	D．They displayed higher insulin levels.

4. What could be learned from the research?

A．A workout after breakfast improves gene performances.

B．Too much workout often slows metabolic rates.

C．Lifestyle is not as important as morning exercise.

D．Physical exercise before breakfast is better for health.

5 . 阅读下面短文，在空白处填入1个适当的单词或括号内单词的正确形式。

Up to 82 percent of children with healthy mothers are not easy to be obese（肥胖的）, according to research. A mother,     1     has a healthy weight, exercises regularly, eats a healthy diet, doesn’t smoke and only     2    (drink) wine in moderation, is significantly less likely     3    (have)a fat child, scientists say.

And research suggests it could be more to do with nurture(养育)    4     nature, as a mother's lifestyle appears     5    (direct) linked to the health of her child. When both mother and child follow a healthy lifestyle, the risk of obesity     6    (reduce)even more, the study of more than 24,000 children found.

The study examined the medical history and lifestyles of more than 24,000 children aged nine     7     fourteen, born to almost 17,000 women in the US. Researchers looked at the link between overall mother health and likelihood of a child     8    (be) obese.

The mother's health was judged on her height-to-weight ratio(比例), her diet, amount of physical     9    (active), smoking status and how much alcohol she drank. A healthy weight and diet, regular exercise, no smoking and moderate drinking all reduce the chance of a woman having     10     obese child.

6 . Hollywood’s theory that machines with evil(邪恶) minds will drive armies of killer robots is just silly. The real problem relates to the possibility that artificial intelligence(AI) may become extremely good at achieving something other than what we really want. In 1960 a well-known mathematician Norbert Wiener, who founded the field of cybernetics（控制论）, put it this way: “If we use, to achieve our purposes, a mechanical agency with whose operation we cannot effectively interfere(干预), we had better be quite sure that the purpose put into the machine is the purpose which we really desire.”

A machine with a specific purpose has another quality, one that we usually associate with living things: a wish to preserve its own existence. For the machine, this quality is not in-born, nor is it something introduced by humans; it is a logical consequence of the simple fact that the machine cannot achieve its original purpose if it is dead. So if we send out a robot with the single instruction of fetching coffee, it will have a strong desire to secure success by disabling its own off switch or even killing anyone who might interfere with its task. If we are not careful, then, we could face a kind of global chess match against very determined, super intelligent machines whose objectives conflict with our own, with the real world as the chessboard.

The possibility of entering into and losing such a match should concentrate the minds of computer scientists. Some researchers argue that we can seal the machines inside a kind of firewall, using them to answer difficult questions but never allowing them to affect the real world. Unfortunately, that plan seems unlikely to work: we have yet to invent a firewall that is secure against ordinary humans, let alone super intelligent machines.

Solving the safety problem well enough to move forward in AI seems to be possible but not easy. There are probably decades in which to plan for the arrival of super intelligent machines. But the problem should not be dismissed out of hand, as it has been by some AI researchers. Some argue that humans and machines can coexist as long as they work in teams—yet that is not possible unless machines share the goals of humans. Others say we can just “switch them off” as if super intelligent machines are too stupid to think of that possibility. Still others think that super intelligent AI will never happen. On September 11, 1933, famous physicist Ernest Rutherford stated, with confidence, “Anyone who expects a source of power in the transformation of these atoms is talking moonshine.” However, on September 12, 1933, physicist Leo Szilard invented the neutron-induced(中子诱导) nuclear chain reaction.

1. Paragraph 1 mainly tells us that artificial intelligence may         .

A．run out of human control

B．satisfy human’s real desires

C．command armies of killer robots

D．work faster than a mathematician

2. Machines with specific purposes are associated with living things partly because they might be able to        .

A．prevent themselves from being destroyed

B．achieve their original goals independently

C．do anything successfully with given orders

D．beat humans in international chess matches

3. According to some researchers, we can use firewalls to           .

A．help super intelligent machines work better

B．be secure against evil human beings

C．keep machines from being harmed

D．avoid robots’ affecting the world

4. What does the author think of the safety problem of super intelligent machines?

A．It will disappear with the development of AI.

B．It will get worse with human interference.

C．It will be solved but with difficulty.

D．It will stay for a decade.