6 . As your alarm clock rings, you slowly open one eye. It seems like it was only a few hours ago that you finished your homework. You close your eyes for just five more minutes, but then your mom knocks on the door. “Time to get up, or you’ll miss the bus!” she says.

If this sounds familiar, you’re not alone. According to a survey, nearly 60 percent of middle school students in the U. S. aren’t getting the recommended 8.5 to 9.5 hours of sleep a night.

How does it happen? In fact, starting the school day too early can take away much-needed sleep from teenagers. Studies show that well-rested teenagers are more likely to get good grades and less likely to suffer from depression (抑郁). Besides, teenagers fall asleep later at night by nature. As a result, some students may only get as few as five hours of sleep.

Many people have realised the importance of enough sleep. Schools in several states have changed to later start times in recent years. In New Jersey, a group of students have formed an organization called Later School Start Times. It wants local middle schools to start 30 minutes later.

▲ Many schools say later start times would create a number of problems. There’s a worry that some kids will walk back home in the dark if the school starts later. It will also leave teens with fewer hours for after-school activities and homework. That’s what Erin Isherwood, a parent from California, is worried about. “My son has an exercise class that he really loves at a gym right after school,” she says. “Now he can’t go.”

Considering the advantages and disadvantages of later school start times, it seems a hard choice to make. The early bird catches the worm (虫子). But what if the bird is too sleepy and tired to catch one?

7 . For thousands of years, humans have used names to communicate with one another. We also give names to our pets. Until now there has been few animals naming one another, but a new study suggests that elephants use certain noises to call other elephants.

A few animals, including dolphins (海豚), use sounds that are similar to names. Each dolphin invents a special sound, and other members communicate with it by copying this special call. The new study, led by Michael Pardo, shows that wild African elephants use names in a way that is not just copying sounds and is much closer to the way humans use names.

For the study, the researchers recorded 625 sounds made by wild African elephants in Kenya that they called “rumbles”. This is the most common kind of call produced by elephants, and it can travel as far as 3.7 miles. It takes place at a very low frequency (频率), which means humans can’t hear it.

The scientists studied the sounds and found that some rumbles were directed at certain elephants to get their attention. They found that all the elephants in the group used the same call to get a certain elephant’s attention. Also, unlike the way dolphins communicate, the rumbles were not just imitations (模仿) of the elephants they were trying to communicate with.

The researchers then played back some of the recorded rumbles to the elephants. They found that elephants responded more to their own name than to other calls. Caitlin, an elephant expert, said the study shows that elephants can still keep in touch with one another even across a large area. She told Live Science, “It allows them to spread out much further and still communicate with each other.”

8 . ①Everyone has goals and most people believe practising repeatedly will help us get a success. Actually, when we reach an acceptable and automatic (无意识的) performance, the additional (额外的) practice won’t make us improve. Suppose we’re learning to play the piano. At first, we know nothing. After taking lessons, we can gain skills as soon as we just practise a few times. Unluckily, after we can play some pieces well with little thoughts, we may find some weak points don’t disappear no matter how often we practise. That’s because automatic abilities will weaken without making efforts on purpose.

②So what do we need if we want to get further improvement? Purposeful practice could be a successful method. It’s different from just practising repeatedly. It has the following features.

③ ▲ It’s all about putting a large number of small steps together to reach a longer-term purpose. For example, passing your piano exam is not a clear goal. It may not guide you to practise effectively (有效地). You will be more successful if you change it into: “Play this piece of the music at a proper speed without a mistake three times.” That’s because it’s easier to judge whether this practice has led to a success.

④Feedback also plays an important role in purposeful practice. It’s a kind of information about how good your performance is. You have to know whether you are doing something right. If not, how you can correct it. Without feedback, you cannot find out what you need to improve or how close you get to your goals.

⑤Another key to achieving purposeful practice is getting out of your comfort zone. It means trying to do something that you couldn’t do before. Most of us like practising what we’re good at. In fact, it’s useless to focus on something we’ve already known. Getting out of comfort zone isn’t about “trying harder,” but about “trying differently”. For example, a professional striker (足球前锋) needs to practise not only shooting, but also other football skills like goalkeeping.

⑥Purposeful practice isn’t everything, but if you want to keep improving, it can be more useful than usual methods.

9 . Have you noticed that people speak differently to babies compared to adults? Caregivers, especially mothers, change their speech when talking to young children. How? Their speech includes higher pitches (音高) and a wider pitch range (范围). They use shorter sentences and repeat words more often. You can think of it as baby talk. Researchers have recently discovered that dolphins also use baby talk with their babies.

The research team recorded sounds of 19 mother dolphins living in the Sarasota Bay area. The sounds of the same female dolphins were compared when they were with and without their babies. Chart 1 shows the sound of a female dolphin without her baby. The researchers found that when dolphins were with their babies, dolphin mothers had a wider range of frequencies (频率) of the sound —the maximum (最高) frequencies were higher and the lowest frequencies were lower.

The findings mirror the way that humans change the speech when speaking to babies. Dolphin “baby talk” may have a similar purpose to human “baby talk”: it may help babies learn how to phonate. We humans don’t only “baby talk” with little babies, but with the children who are still learning to speak. As a result, our children are able to talk. That’s exactly what happens to dolphins. The changes in speech don’t just happen when dolphin mothers stay with very young babies, but also between mothers and babies that are closer to “toddler (蹒跚学步的)” age. Another possible reason for using specific pitches is to catch the children’s attention. It’s really important for a young dolphin to know “Oh, mum is talking to me now.”

The research about baby talk in dolphins reminds us how important it is in humans. Whenever we speak with a young child, how we say things could be as important as what we say.

A．	B．
C．	D．

10 .

Perhaps, it’s more French than the Eiffel Tower. It’s carried home by millions each day. It is the baguette, which has been the biggest food symbol of France for a long time. Data shows the French eat about 320 baguettes every second and more than 6 billion baguettes are sold every year in France. At the same time, only 550 million hamburgers are sold in France each year.

It wasn’t until 1920 that the baguette got its name but its history goes back much further. The long, thin bread was firstly made in the mid-18th century. In 1893, steam oven was introduced to Paris, which made the bread more delicious. In the 1920s, a law stopped bakers (烘焙师) working before 4 am. To prepare the breakfast in time, the baguette became their only choice. Thus, in the 1930s, it became popular across France. Today, it remains an important part of French culture.

Unluckily, the baguette has been facing great challenges these years. With more supermarkets appearing, France has lost 400 traditional bakeries (面包房) every year since 1970. What’s worse, the war between Russia and Ukraine has increased the price of flour — one of the four ingredients (原料) to make the baguette. The price of the baguette is doubled as well. Many people aren’t willing to pay that much. Besides, some bakers can’t afford to turn on their ovens because of the increasing energy prices.

To protect this food culture, UNESCO put the baguette to its List of Intangible Cultural Heritage (非物质文化遗产) not long ago. Will it bring a bright future to the baguette? “This news won’t help us survive the winter,” said Pascale Giuseppi, the owner of a bakery, “I still have bigger bills to pay. I’d better turn off my oven for good.”