阅读下列短文，从每题所给的四个选项 （A 、B 、C  和 D ）中，选出最佳选项。

When I lived in Spain, some Spanish friends of mine decided to visit England by car. Before they left, they asked me for advice about how to find accommodation. I suggested that they should stay at "bed and breakfast" houses, because this kind of accommodation gives a foreign visitor a good chance to speak English with the family. My friends listened to my advice, but they came back with some funny stories.

"We didn't stay at bed and breakfast houses," they said, "because we found that most families were on holiday." I thought this was strange. Finally I understood what had happened. My friends spoke little English, and they thought "VACANCIES" meant "holidays", because the Spanish word for "holidays" is said "vacaciones". So they did not go to house where the sign outside said "VACANCIES", which in English means there are free rooms. Then my friends went to houses where the sign said "NO VACANCIES", because they thought this meant people who owned the house were not away on holiday. But they found that these houses were all full. As a result, they stayed at hotels.

We laughed about this and about mistakes my friends made in reading other signs. In Spanish, the word "DIVERSION" means "fun". In English, it means that workmen are repairing the road, and that you must take a different road. When my friends saw the word "DIVERSION" on a road sign, they thought they were going to have fun. Instead, the road ended in a large hole.

English people have problems too when they learn foreign languages. Once in Paris when someone offered me some more coffee, I said "Thank you" in French, I meant that I would like some more, however to my surprise the coffee pot was taken away! Later I found out that "Thank you" in French means "No, Thank you".

    Nearly 19 percent of teachers of color (有色人种教师) left their jobs after the 2014-2015 school year. Some left for personal reasons like taking care of their families. But 50 percent said they left because they were dissatisfied with their employment situation, such as poor working conditions, student discipline problems and large class sizes. Thus, taking immediate measures to improve it is our top priority.

    For years, researchers have proved the benefits of increasing the share of minority teachers in schools, especially as our public school system has turned to one that is made up mostly of minority students. Teachers of color, who are more likely than their white counterparts to choose to work in racially diverse (多种多样的) schools, offer particular benefits to their students. Graduation rates increase among minority students when they are taught by racially similar educators, research shows. They can also serve as positive role models, and their presence reduces the chance of racial discrimination at school.

    The Shanker Institute report suggests that the rate of minority teacher hiring is not the whole problem. The problem is what happens after these teachers enter the classroom. These teachers often work in high-poverty rural schools. They are more likely to have less-desirable working conditions.

    Diversity is a key component to equality and opportunity. Where there's a diverse teaching workforce, all kids thrive. So solutions must be found at once to turn this trend around. Firstly, schools should develop mentorship programs that support minority teachers once they are in the classroom. Secondly, more money should be spent in improving working conditions in these schools. Of course, school headmasters should also be evaluated on their ability to retain teachers of color.

    Getting less sleep has become a bad habit for most American kids. According to a new survey by the National Sleep Foundation, 51% of kids aged 10 to 18 go to bed at 10 pm or later on school nights, even though they have to get up early. Last year the Foundation reported that nearly 60% of 7- to 12-year-olds said they felt tired during the day, and 15% said they had fallen asleep at school.

    How much sleep you need depends a lot on your age. Babies need a lot of rest: most of them sleep about 18 hours a day! Adults need about eight hours. For most school-age children, ten hours is ideal. But the new National Sleep Foundation survey found that 35% of 10- to 12-year-olds get only seven or eight hours. And guess what almost half of the surveyed kids said they do before bedtime? Watch TV.

    “More children are going to bed with TVs on, and there are more opportunities(机会) to stay awake, with more homework, the Internet and the phone,” says Dr. Mary Carskadon, a sleep researcher at Brown University Medical School. She says these activities at bedtime can get kids all excited and make it hard for them to calm down and sleep. Other experts say part of the problem is chemical. Changing levels of body chemicals called hormones not only make teenagers' bodies develop adult characteristics, but also make it hard for teenagers to fall asleep before 11 pm.

    Because sleepiness is such a problem for teenagers, some school districts have decided to start high school classes later than they used to. Three years ago, schools in Edina, Minnesota, changed the start time from 7:25 am to 8:30 am. Students, parents and teachers are pleased with the results.

    Philadelphia offers a ton of attractions that are suitable for people of every age and here are some family—friendly attractions.

    Spruce Street Harbor Park

    Spruce Street Harbor Park, one of the best urban beaches in American, is an outdoor heaven on the Delaware River waterfront. Visitors can relax in a hammock, play on the playgrounds, and play games like table tennis and giant chess. Don't miss out on the park at night, when colorful LED lights hanging from treetops make the entire area bright.

    Blue Cross RiverRink

    Offering ice skating in the winter and roller skating in the summer, Blue Cross RiverRink creates a fun，outdoor experience for the whole family. Visitors can play on the nine-hole mini-golf course during the summer, and enjoy eats and drinks from the on-site (现场的) bar and restaurant all year round.

    Sesame Place

    Big Bird, Elmo and the other stars of Sesame Street come out and play at Sesame Place, the only theme park in the nation starring the popular TV show's most lovable characters. A water park, interactive activities，parades, fireworks and shows add to the fun.

    Once Upon a Nation Storytelling Benches

    On summer days, uniformed and professional storytellers at 13 storytelling benches throughout Philadelphia's Historic District entertain visitors with true, free, three-to-five minute tales about the colonial (殖民的）era as part of Once Upon a Nation . Children can pick up a Story Flag at any storytelling bench, and then collect a star from every storyteller on their journeys. Flags with all the stars can get free rides on the Parx Liberty Carousel at Franklin Square.

    Throughout history scientists have risked their health and their lives in their search for the truth.

    Sir Isaac Newton, the seventeenth century scientist, was very smart, but that didn't stop him from doing some pretty stupid things. In his laboratory in Cambridge he often did the strangest experiments. Once, while testing how light passes through lenses (晶状体), he put a long needle into his eye, pushed it to the back, and then moved it around just to see what would happen. Luckily, nothing long-lasting did. On another occasion he stared at the sun for as long as he could bear, to discover what effect this would have on his sight. Again he escaped suffering permanent damage, though he had to spend some days in a darkened room before his eyes recovered.

    In the 1750s the Swedish chemist Karl Scheele was the first person to find a way to produce phosphorus (磷). He in fact discovered eight more chemical elements including chlorine (氯), though he didn't get any praise for them. He was a very clever scientist, but his one failing was a curious habit of tasting a little of every substance he worked with. This risky practice finally caught up with him, and in 1786 he was found dead in his laboratory surrounded by a large number of dangerous chemicals, any of which might have been responsible for his death.

    Eugene Shoemaker was a respected geologist. He spent a large part of his life studying craters (火山口) on the moon, and how they were formed, and later did research into the comets of the planet Jupiter. In 1997 he and his wife were in the Australian desert where they went every year to search for places where comets might have hit the earth. While driving in the Tanami desert, normally one of the emptiest places in the world, another vehicle crashed into them and Shoemaker was killed on the spot. Some of his ashes (骨灰) were sent to the moon aboard the Lunar Prospector spacecraft and left there — he is the only person who has had this honor.

    "What kind of rubbish are you?" This question might normally cause anger, but in Shanghai it was brought about weary complaints over the past few months. On July 1st, the city introduced strict rubbish-sorting regulations that are expected to be used as a model for our country. Citizens must divide their waste into four separate categories and put it into specific public bins. They must do so at scheduled times, when monitors are present to ensure that rules are obeyed and to examine the nature of one's rubbish.

    Violators could be hit with fines of up to 200 yuan ($29). For repeat violators, the city can add black marks to their credit records, making it harder for them to obtain hank loans or even buy train tickets.

    Shanghai authorities are responding to obvious environmental problem. It produces 9 million tons of garbage a year. But like other cities in china, it lacks a recycling system. Instead, it has relied on rubbish pickers to pick out whatever can be reused. This has limits. As people get wealthier, fewer of them want to do such dirty work. The waste, meanwhile, just keeps piling up. China produces 80 billion pairs of one-off chopsticks a year.

    Many citizens appear to support the idea of recycling in general but are frustrated by the details. Rubbish must be divided according to whether it is food, recyclable, dry or hazardous(有害的), the distinctions among which can be confusing, though there are apps to help work it out. Some have complained about the rules surrounding food waste. They must put it straight in the required public bin, forcing them to tear open plastic bags and toss(投掷）it by hand, Most annoying are the short periods for throwing trash, typically a couple of hours, morning and evening. Along with the monitors at the bins, this means that people go at around the same time and can keep an eye on what is being thrown out; no one wants to look bad.