With the approval of the Singapore government, a company called nuTonomy has become the first-ever to test self-driving cars with the public. Interested people could sign up for a free trial run at no cost. When they received an invitation from the company, they could book a ride on the driverless taxi service from their smartphones.Not surprisingly,the rides proved very popular,with dozens of customers eagerly trying out the cars each day.

    Driverless cars are a great option for those who do not know how to drive and for those who do not enjoy driving.Some researchers even believe that such cars can make road travel safer by reducing human errors.But since driving requires many of our senses to be on alert（高度警觉）, replacing that by machines is easier said than done.

    The environment in which cars operate is constantly changing—from roads and pedestrians to co-travelers. A driverless car needs special equipment to analyze its surroundings. Then, it must translate that information into a practical route and safe travel. To be truly autonomous, a car has to do this independently without human input. Today, some cars have a certain degree of autonomous functions. But even the completely automated vehicles still require a driver to take back control under uncertain conditions.

    The island city-state is well known for excellent roads and drivers who obey the rules. This has made it ideal for real-world testing and feedback. The government has encouraged research in autonomous vehicles, since it can improve safety and potentially reduce the traffic burden as well.

    Here we introduce some rental houses to you.

    Apartment Levant in Komiza

    Overlooking one of the most beautiful fishing villages in Croatia, our two-storey house also gives you a full view of Komiza bay as well as neighboring island of Bisevo.The apartment has a wide，covered balcony and a small garden with lemon trees. It is only 10 minutes' walk from the centre of the village, although it is on the edge of the village, with forests behind the house.

    Apartment Domina

    Located in the centre of the city, the apartment is protected as a historical site. All other facilities are at your fingertips such as restaurants, shops and museums. The apartment is fully equipped and air-conditioned, having a kitchen with a dishwasher, a satellite TV and the free Web access. It contains a bedroom with a double bed and antique furniture. Besides, the apartment offers pet-friendly accommodation.

    Apartment Tonka

    The apartment is located in an old stone house in the centre of Komiza. It offers two bedrooms, each with a separate bathroom, and a living room with a furnished kitchen. The house is only a couple of minutes away from the old harbor, along the old town's street where you can enjoy Komiza's rich cultural history. The bus stop is less than 200 meters away, near the fruit and vegetable market.

    Pearl of Issa

    This two-bedroom apartment is only a few minutes' walk from beautiful beaches, shops, restaurants, cafés and bars. It consists of two bedrooms, a fully equipped modern kitchen, a dining room and a resting area with a sofa, which can be used as an extra sleeping place for one person, a bathroom and a balcony with comfortable garden furniture and barbecue equipment.

    Let me tell you, Johnson, this is going to be the biggest development in animal-imitative cybernetics (动物模仿控制学) since Hayes pioneered the field way back in 2014. Everybody's going to want a piece of my discovery! Everyone! Even United States of Earth Defense! I'm going to be the richest man alive!

    I can see you don't share my excitement yet. Just wait, old friend. Accompany me to my lab, and we will see who has the last laugh. You'll be begging me to take you on as a lab assistant after I...Oh, here we are. You first, my good man. You see, I had already come up with the perfect cybernetic engine, able to copy any life form. The question was, which creature would be the best show of my discovery? I've used a life form nobody's considered for cybernetics. It is powerful, graceful, intelligent, and best of all people love it. I chose the tiger!

    Go on, have a glance! Ha! Don't look so shocked, Johnson. I leave it powered down when I'm not testing it. It is rather great, though. Yes, all the latest technology, including claws (爪) I had made from vanadium alloy (合金). It cuts through steel like its wet cardboard. The process that I used to get its mind in the computer will be enough to ensure me fame and fortune.

    Huh? It did move, didn't it? I guess I left it on yesterday. No, don't look so nervous; I can shut off its main power with this remote (遥控器) right here. Nothing to worry about. I really don't think it's regarding you as a meal. Be reasonable, old...Oh, God! Johnson! The remote, where is it? Where?!

    Ah, there we go! Too late to save Johnson, though. What a pity. Better safe than sorry. There! God, what a mess. Even worse, I can't call the police now; the bad publicity would overshadow my breakthrough, and certainly frighten the investors. I've got to get rid of the body secretly, somehow. I could bury it, but I might be seen. I could burn it, but the smoke would be very doubtful. What to do?

    What to...

    I wonder...How fast can this cat eat?

    Some educators told us that more years of school could help students get higher scores on intelligence tests. That was a finding of a study of teenage males in some countries. Now, another research shows that physical activity may help students do better in their classes.

    The research comes as educators in some countries are reducing time for activities like physical education. They are using the time instead for academic(学术的) subjects like math and reading. The studies appeared between 2008 and 2014. They included more than 55,000 children, aged 6 to 18.

    Amika Singh: "According to the results of our study, we can conclude that being physically active is beneficial for academic performance. There are, first, Physiological explanations, like more blood flow, and so more oxygen to the brain. Being physically active means there are more hormones(荷尔蒙) produced like endorphins(内啡肽). And endorphins make your stress level lower and your mood improved, which means you also perform better."

    Also, students taking part in organized sports learn rules and how to follow them. This could improve their classroom behavior and help them keep their mind on their work.

    The study leaves some questions unanswered, however Ms Stash says it is not possible to say whether the amount or kind of activity affected the level of academic improvement. This is because of differences among the studies.

    The researchers said they found only two high­quality studies. They needed more high­quality studies to confirm(证实) their findings. They also pointed out that "results for other parts of the world may be quite different".

    Still, the general finding was that physically active kids are more likely to do better in school. Ms Singh says schools should consider that finding before they cut physical education programs. Her paper on "Physical Activity and Performance at School" is published in the Archives of Pediatric and Adolescent Medicine.

    In my senior year of high school, I got a part-time job working at the local coffee shop. One miserable rainy day, Hank, one of my regular customers came in looking depressed and defeated. My co-worker and I asked what the problem was and if we could help, but he said he wouldn't want to tell any details. He just felt like going into bed, pulling the sheet up over his head, and staying there for a few years, and I knew exactly how he felt.

    Before he left, I handed him a bag along with his iced coffee. He looked at me questioningly because he hadn't ordered anything but the coffee. He opened the bag and saw that I had given him his favorite type of doughnut (油炸圈饼).

    "It's on me,"I told him."Have a nice day."

    He smiled and thanked me before turning around and heading back out into the rain.

    The next evening, when I was in the middle of making coffee, Hank drove up to the window. But instead of ordering anything, he handed me a single pink rose and a little note. I waited until I saw his Jeep leave the parking lot, then I ran to the back of the shop and read the note. It read:

    Christine,

    Thanks for cheering me up yesterday. It is so nice to meet someone that's genuinely sweet, warm and thoughtful and unselfish. Please don't change your ways because I truly believe that you will succeed. Have a great day!

    Hank

    As time went on, I did come across more complaining customers. But anytime I felt depressed, I thought of Hank and his kindness. Then I would smile, hold my head up high, clear my throat and ask politely," How can I help you?"

Isatou Ceesay was born in 1972 in a small village in Gambia, Africa. As a teenager, Ceesay was forced to drop out of school because of poverty. She carried some goods with many girls like her to sell in the market to raise herself At that time, the plastic bags, being strong and light, became popular in Gambia. The problem was that people did not reuse the bags and simply threw them behind their homes. Over time, the houses were surrounded by trash.

Ceesay lived in such an environment for many years. She kept learning from the surrounding environment and planned to take action to change. In 1997, she started a recycling movement called One Plastic Bag in Gambia. She educated women in Gambia to recycle plastic waste into income for themselves. In the beginning, the movement had a mission to educate their village colleagues about the need to reuse garbage and recycle plastic waste, rather than letting the garbage increase behind their homes.

Over time, the movement became big and able to support and provide income for women around. It was also able to greatly reduce plastic waste in Gambia. But the work of collecting trash turned to be taxing. During the rainy season, plastic waste became wet and difficult to take, and after that it still took patience to dry it before it could be processed.

Ceesay said, "As a habit, people are used to pouring their garbage behind their houses, and because it is not visible, they forget it. But the bad effects again knock on your door very quickly — dirty air, various diseases and so on. Of course, if one man's house is clean but his neighbor's is not, then the man is also not healthy."

For 17 years, Ceesay has contributed to one of the most important problems about the plastic waste. In 2012, she got the TIAW Difference Maker Award in Washington, DC, United States. Her story was written into a book, which inspires many others to join or become makers of change in their own communities.