Mrs. Turner's telephone number was 3463, and the number of the cinema in town was 3464. People often made mistakes and telephoned her when they actually wanted the cinema.

    One evening the telephone bell rang and Mrs. Turner answered it. A tired man's voice came over the telephone, “At what time does your last film begin?” “I'm sorry,” said Mrs. Turner, “but you have the wrong number. This is not the cinema.” “Oh, it began twenty minutes ago? ” said the man. “I'm sorry about that. Well, goodbye.” Mrs. Turner was very surprised, so she told her husband. He laughed and said, “No, that wasn't a mistake. The man's wife wanted to go to the cinema, but he was feeling tired, so he telephoned the cinema. His wife heard him, but she didn't hear you. Now they will stay at home this evening, and the husband will be happy!”

Lisa: My best teacher is my geography teacher in 10th grade. Why? Because we did school projects! Back then I wrote about India and never forgot what I had learned. He brought the culture to life by letting me become part of it. He also listened to us and was always ready with a kind word.

David: My best teacher is my high school social studies and history teacher, Thomas Ladenburg. He respected us, though we were just teenagers. His class was never boring because he often asked us to discuss in class. He used his own materials which made the class very interesting.

Henry: My best ever teacher is my biology teacher in high school. I really liked her class. She explained everything very clearly. She also checked our notebooks to make sure we had written down what she said. Now, many years later, I can still remember a large part of the things she taught!

Susan: The best teacher I have ever had is my 10th grade social studies teacher. She was always in a good mood and kept us laughing. She was really young, so she acted like us teenagers, which made learning fun. If we needed to talk to an adult about a problem, we would always come to her because we knew she could help us.

Tom: My favourite teacher is Mr. Yelle. He taught us math, science and music. He spoke to us “at eye level”, and was very patient and kind. We did great projects for the science fairs. Forty years later, I still remember his lessons very well. By the way, though he was called Mr Yelle, he didn't yell(喊叫).

    Humans have been keeping animals as pets for tens of thousands of years, but Dr. Jean-Loup Rault, an animal scientist at the University of Melbourne in Australia, believes new companions are coming: robot pets.

    “Technology is moving very fast,” Rault told ABC News, “The Tamagotchi in the early 1990s was really the first robotic pet, and now Sony and other big companies have improved them a lot.”

    This may not sit well with pet lovers. After all, who would choose a plastic toy over a lovely puppy? But Rault argues that the robotic kind has a lot going for it: “You don't have to feed it, you don't have to walk it, it won't make a mess in your house, and you can go on a holiday without feeling guilty.” The technology also benefits those who are allergic to pets, short on space, or fearful of real animals.

    It's not clear whether robot pets can replace real ones. But studies do suggest that we can bond with these smart machines. People give their cars names and kids give their toy animals life stories. It's the same with robots. When Sony stopped its repair service for its robot dog Aibo in March 2014, owners in Japan held funerals.

    As an animal welfare researcher, Rault is concerned about how robotic pets could affect our attitudes towards live animals. “If we become used to a robotic companion that doesn't need food, water or exercises, perhaps it will change how humans care about other living beings,” he said.

    So are dogs and cats a thing of the past, as Rault predicts? For those who grew up with living and breathing pets, the mechanical kind might not do. But for our next generation who are in constant touch with smart technology, a future in which lovely pets needn't have a heartbeat might not be a far-fetched dream.

    Kirby Wildlife Park — Keeper Experience

    Due to the large number of inquiries from people interested in working with animals, Kirby Wildlife Park has set up the unique 'Keeper Experience' package. The fantastic experience is available to anyone over the age of 18 who is reasonably fit. We regret that for health and safety reasons, participants who are pregnant, in a wheelchair or suffering from illnesses cannot take part.

A typical day

9:15        Arrival

9:30         Health and Safety Briefing

10:00        Apes and Monkeys

    While cleaning out the enclosure (围场) you will find out about how enclosures are enriched with novel items and new smells to stimulate (刺激) the animals' senses and imitate their natural environment.

12:00       Lunch

14:00        Big Cats

    On the highlight of most volunteers' day, you will feed the cats and learn about their nutritional needs. The keeper will give you an introduction to how cat behaviour can be read to get an idea of their welfare and health.

16:30        Meet the Team

    Meet more of the staff and learn how you can get further involved with work at the park. Learn about our animal adoption plan, what it takes to be a good keeper and where to obtain the right qualifications for a career in animal welfare.

Booking and cancellation

    The Keeper Experience is available on Mondays, Wednesdays and Fridays throughout the year, and must be booked at least two weeks in advance. Full payment is needed when booking.

    Cancellations must be made more than fourteen days before the event, or you won't receive a full refund.

    City trees grow faster and die younger than trees in rural forestry, a new study finds. Over their lifetimes, then, urban trees will likely absorb less CO₂ from the air than forest trees.

    As we all know, the earth would be freezing or burning hot without CO₂. However, CO₂ is a greenhouse gas, meaning it traps energy from the sun as/heat. That makes temperatures near the ground rise. Human activities, especially the widespread burning-of fossil(化石)fuels, have been sending extra greenhouse gases into the air. This has led to a rise in average temperatures across the globe.

    Studies had shown forests readily absorb CO₂, but there hadn't been much data on whether city trees grow, die and absorb CO₂ at the same rate as forest trees do. So some researchers decided to find out.

    To figure out how quickly trees were growing, researchers tracked their diameters (the width of their trunks) between 2005 and 2014. A tree's diameter increases as it grows, just as a person's waist size increases as they gain weight. About half the weight of a tree is carbon, research has shown. Most of the rest is water. Over the nine years' tracking, the researchers found city trees absorbed four times as much carbon from the air as forest trees. However, they were twice as likely to die. So over the lifetime of each type of tree, forest trees actually absorbed more CO₂.

    City trees grew faster because they had less competition for light from their neighbors. In a forest，trees tend to grow close together，shading their neighbors. Street trees also benefit from higher levels of nitrogen (氮)in rainwater. Nitrogen helps plants grow. Waste gases from gas-burning cars also contain nitrogen, thus enriching city air with nitrogen. Later, rainwater may wash much of it to the ground. Some street trees may also have better access to water than trees in the country because the underground water pipes can leak.

In a long-sleeved shirt and jeans, Dieudonne Twahirwa looks nothing like the traditional African farmer. The 30-year-old owner of Gashora Farm knows what a difference that makes.

"You need more role models," he said, standing among knee-high rows of chili (辣椒) plants. "If you have young farmers, they have land and they drive to the farm and others may think, ‘Why can't I do that?"

Twahirwa, a university graduate, bought a friend's tomato farm six years ago for $150. He made $1,500 back in two months. "You have to link farming with entrepreneurship (创业精神) and real numbers," he said.

Many young Africans are quitting countryside areas, choosing not to work hard for a long time in the fields-a job made a lot tougher by climate change. But Twahirwa is one of a growing group of successful farmers working to improve agriculture's image on the continent. Some 1,000 farmers now produce chilies for him. He is starting a fourth farm of his own, and exports fresh and dried chilies and oil to Britain, the United States, India and Kenya.

Africa has the world's youngest population and 65 percent undeveloped farmland. Yet accessing land and loans is difficult, and African productivity is low with crop output just 56 percent of the international average.

"Agriculture is mainly connected with suffering and no young person wants to suffer," said Tamara Kaunda, an expert of FAO. She believes African agriculture needs a change to get rid of its old-fashioned image of extremely difficult and tiring work with a hoe (锄头). "Show young people with tractors, green fields, nice irrigation systems and smartphones," she said.

Getting young people involved in agriculture does not mean they have to work on a farm. For example, in coffee production, the beans go from the farm to the washing station, then to be separated from the outer coverings. There are people in the coffee value chain who just build washing stations and rent them out. You just have to find a place to plug in.