Light travels at a speed which is about a million times faster than the speed of sound. In one second, light travels about 300,000 km, but sound travels only 344m. You can get some idea of this difference by watching the start of a race. If you stand some distance away from the starter, you can see smoke come from his gun before the sound reaches your ears. This great speed of light produces some strange facts. Sunlight takes about 8 minutes to reach us. If you look at the light of the moon tonight, remember that the light rays（光线）left the moon 1.3 seconds before they reached you. The nearest star is so far away that the light which you can see from it tonight started to travel towards you four years ago at a speed of nearly 2 million km per minute. In some cases the light from one of tonight's stars started on its journey to you before you were born.

    Thus, if we want to be honest, we cannot say “The stars are shinning tonight.” We have to say, “The stars look pretty. They were shining four years ago but their light has only just reached Earth.”

根据短文内容，选择最佳答案，并将选定答案的字母标号填在题前括号内。

    New friends. Fresh lifestyle. Better career opportunities…Those are attractions of overseas study for young people in China. “Start early, finish strong,” some of them say.

    More than 300 universities from 27 countries and regions were represented at last weekend's international education exposition(展览).

    If you make a list of the world's top ten most challenging jobs,chances are that being a teacher will not make the cut.But think about the discouraging task millions of educators face each day as they try to shape a group of often bad-tempered,wild kids into intelligent,well-rounder individuals.That surely has to be the toughest job in the world, especially given that there is no promotion or bonus awaiting them even if they are wildly successful!

    What if there all-important individuals that we often take for granted（想当然）disappear from our lives?That was what Project Ed and Participant Media's Teach campaign asked filmmakers of all ages to imagine in their recently-held competition.Entitled "A World Without Teachers",its purpose was to inspire more young people to become teachers.However,the 62 amazing video submissions also serve as a reminder of how horrible things would be if we didn't have these selfless individuals guiding us through life.What was interesting is that even the youngest participants did not appear to be happy at the idea of not having anybody telling them what to do.

    High-school student Savannah Wakefield reflected if art as we know it today would have been different without teachers.Would Monet have discovered his talent for impressionism?Los Angeles-based Miles Horst,who won the 1000 USD prize for the best adult submission imagines a world where teachers are replaced by a “brain box” in his fun lively entry.

    Youth category winner Marina Barham's video represents a fact we all know but often forget.Teachers don't just teach,they inspire something that no electronic device,no matter how smart,can do!So the next time you think your teacher is being "mean" for trying to channel you in the right direction,imagine a life without him/her.We have a feeling it will not appear as rosy!

Dear Editor,

    I'm a Senior 1 student in a middle school. This term, my favourite teacher, Miss Mao, no longer teaches us. I want to see her, but I'm afraid that she no longer likes me and I don't want to trouble her. I really miss her. What should I do?

Tian Yan

Dear Tian Yan,

    It's bad luck that you have lost your favourite teacher. But, if she is still in your school, nothing can stop you going to see her. When she isn't busy, ask her if she minds having a quick chat. You can then tell her she was your favourite teacher. Everyone is happy to know they are liked!

    If she has left the school, it will be more difficult to meet her. It will be hard, but remember people always come and go in our lives. We can't depend on them being with us all the time.

    You may be sad to say goodbye to her, but we can remember and learn from her. Think of her best qualities.    

    You could also try looking for similar qualities in your other teachers. Study hard and give your new teacher a chance. In time, you might start to see that he or she has different qualities to learn from.

    Finally, you can not completely depend on other people getting you through your studies, or even your life.

Editor

    Americans think that everything we British people say sounds smart. We think that they sound low-class, but secretly we think they sound cool. These are just stereotypes about British and American English, but there is some truth in them.

    What is certainly true is that the differences between British and American English continue to interest us.

    When the US was only around 20 years old, people were already saying that British accents sounded more intelligent, according to Erin Moor's book. That's Not English: Britishisms, Americanisms, and What Our English Says About Us.

    However, there are many different accents in Britain—Moor says the UK may have just as many regional accents as the US, even though the population is around one-fifth the size. In the UK, accents are much more related to class, but to many Americans, even an accent that British people think is “low class” is thought of as intelligent and superior, according to MPR News.

    American slang has been part of British people's vocabulary for a long time—the amount of American television, movies and music enjoyed in the UK means that British people have been using words like “cool” and “awesome” for years now. But sometimes words from the UK make it to the US—like “gobsmacked”.

    “Gobsmacked” started as slang (俚语) from northern England. “Gob” means mouth, so the word means “surprised as if someone smacked (掌掴) you in the mouth”. Reality television brought it to the US, Moor said. When the singer Susan Boyle became famous for her unlikely great singing voice on the show Britain's Got Talent, she used it all the time. “I'm gobsmacked,” she repeated, and it got popular.

    “Americans love a colourful piece of slang as much as anyone else,” said Moor. And this is just one example of how Britons and Americans can leave each other “gobsmacked” with their different types of English!

    You've heard the old advice that skipping meals is a sure-fire way to ruin a weight loss plan, but a new study presented this week at the annual Obesity Society Meeting in New Orleans suggests that perhaps we've overlooked the benefits of selective fasting. According to the research, eating during a smaller window of time each day and skipping your evening meal could have a positive health effect.

    The study concluded that overweight individuals who ate during the day and fasted during the evening reported fewer hunger swings and burned more fat at night, WebMD reported. However, although this diet plan results in more fat burned in the evenings, it did not seem to increase fat burning overall. Due to this, at this moment it's still unclear as to how this eating schedule can affect general weight loss.

    "At this point, we are not sure whether or not total fat burning is increased," study lead author Courtney Peterson told Medical Daily in a recent email." We will need to do a larger study to find out for certain whether or not time-restricted feeding improves fat burning."

    Still, although the results do not indicate a clear association between nighttime fasting and weight loss, they are still important for the world of nutrition. For example, Peterson told Medical Daily that she was surprised to find that participants did not report being hungrier than average, or have above-average swings in hunger levels, despite fasting daily for 18 hours.

    "So we overturned the belief that fasting for longer period each day when the same number of total calories are eaten makes a person hungrier, "wrote Peterson.

    While the effects of fasting and time-restricted feeding have been studied and proven to work in a rodent(贴齿动物)model, research on human subjects is still in its early stages. For this reason, Peterson explained that it is far too early to say, with factual evidence as backing, that time-restricted feeding will improve weight loss in humans. Still, Peterson explained that practicing this eating behavior does have obvious benefits, such as reducing overall food intake, and suggested that practicing time restricted eating a few times a week could be both practicable and healthy.

    "It could be used for short-term goals or longer-term goals，"concluded Peterson." As far as we know，it is safe for adults，although pregnant women and children should not try it."