Now many young people are traveling around the world on their own，not because they have no one to travel with，but because they prefer to go alone.

    Kristina Wegscheider from California first traveled alone when she was at college and believes that it is something everyone should do at least once in their life. ＂It opens up your mind to new things and pushes you out of your comfort zone.＂ Wegscheider has visited 46 countries covering all seven continents.

    In foreign countries，with no one to help you read a map，look after you if you get ill，or lend you money if your wallet is stolen，it is challenging. This is what drives young people to travel alone. It is seen as character building and a chance to prove that they can make it on their own.

    Chris Richardson decided to leave his sales job in Australia to go traveling last year. He set up a website，The Aussie Nomad，to document his adventures. He says he wished he had traveled alone earlier. ＂The people you meet，the places you visit，or the things you do，everything is up to you and it forces you to grow as a person，＂ said the 30-year-old man.

    Richardson describes traveling alone like ＂a shot in the arm＂，which ＂makes you a more confident person that is ready to deal with anything＂. He said，＂The feeling of having overcome something on my own is a major part of what drives me each day when I'm dealing with a difficult task. I walk around with my head up because I know deep down inside that nothing is impossible if you try.＂

    The great 19th century explorer John Muir once said，＂Only by going alone in silence can one truly get into the heart of the wilderness.＂

    Early people lived by hunting animals and gathering grains. After a tribe(部落） had lived in an area for some time, its food supply would begin to reduce. Then the tribe had to move to new hunting grounds where there was more food.

    This way of life caused special problems for the tribes. They were forced to depend on luck, as well as on their hunting skills. If they could find no game, the whole tribe was in danger of starving. And when the hunters had good luck one day, they were not sure to find game the next time. The tribes moves often because much land was needed to support their people.

    Finally, people learned that they could grow their food. At first, the women of tribes raised patches of wild grain. Later, people discovered that they could plant their own seeds. Farming slowly became a way of life.

    As people turned away from hunting to farming, their life changed. When the food supply became more constant, they no longer moved from place to place. The success of their crops depended partly on the weather, but there were also things they could do to help crops grow.

    In the past, a tribe had to travel many miles for food. Now , only a small amount of land was necessary to feed the whole tribe. The tribe could grow in size because farming provided a way to feed people.

    Would you buy a car that released calming smells into the air when you are stuck in heavy traffic? Would you buy a robot that smells like a human being?

    Many people have seen the 3-D computer-made environments of virtual reality (VR). Now these virtual worlds will not just look and sound real. Researchers have created VR environments that even smell like the real things. With the new technology, users open a virtual door and step into a new environment, like a rainforest. After they enter this virtual world, special equipment releases forest-like smells into the air to make the experience seem more real.

    Suzanne Fisher-Murray said, “it is a really wonderful experience that you have because you're exploring this environment and you have smells with it.”

    In the United States, Smell-O-Vision was designed to provide smells during the showing of a movie. The Smell-0-Vision system was once popular in the 1960s. Now, Emanuela Maggioni says it is close to becoming popular again. “The connection with emotions, memories, and…the sense of smell,” Maggioni said. “It is unbelievable what we can do with technology.”

    The uses for smell technology are not just limited to films and the performing arts. Researchers showed a computer program where users could imagine themselves driving a car. The system included a special smell-spraying machine. Dmitrijs Dmitrenko said, “We want to deliver the smell of lavender（薰衣草）every time the person drives over the speed limit. We choose lavender because it's a very calming smell.”

    Scientists are experimenting with smell instead of sounds or image-based alerts on telecommunications equipment. And businesses are already using smell to influence people's behavior. “Not only.…in stores…But on the other side, you can create and stimulate immediate buying,” Maggioni said. “So you're in a library and you smell coffee and actually you are unconsciously having the need to drink a coffee.”

    Age has never been a problem for 16­year­old Thessalonika Arzu­Embry. After all, she's already got her master's degree.

    The North Chicago­area teen started homeschooling at the age of 4. She began having an influence on others soon after. When she was 6 years old, she was an inspirational speaker at an organization called Tabitha House Community Service, a shelter for people who were forced to leave their homes due to the situations such as earthquake, flood and other natural disasters.

    At the age of 11, she graduated from high school and then earned her bachelor's degree in psychology in 2013. She completed those classes online as she was traveling for church events and leadership meetings.

    She doesn't stop there, though. The teen plans to focus on aviation psychology(航空心理学) for her further study, a decision inspired by her father who is a pilot. She grew up around airplanes and took fights all the time. Her goal is to use it to determine whether pilots are dealing with problems that could have deadly results once the plane takes off­a topic that has been in the news lately. For her, it's a mix of two of her interests.

    In her free time, Thessalonika enjoys playing tennis, swimming and being active in her youth group at church. She also has three self­published books, which are on her site. Jump the Education Barrier is written to help students finish college, and in the future aims to help business owners with trends. Her third book The Genius Race, has a wider appeal. It is designed to help people to be geniuses in various areas of life.

    Angus, Doris, Gabriel and Kamil are some of the 21 names that have been chosen to be given to storms in the UK in the 2016/17 season.

    The Met Office, the UK's national weather service, decided to give storms boys' and girls' names in 2015 in the same way as they did in America.

    The Met Office hopes that naming big storms will mean people are more aware (意识到) of them and how dangerous they can be. Derrick Ryall, from the Met Office, said, "We have seen how naming storms elsewhere in the world raises people's awareness of storms before they break."

    In the past, the same UK storm could be given different names by different organisations. "We noticed that many organisations during the last couple of winters, when we have had bad storms, started giving names to them. Think back to the St Jude's Day storm in 2013, and the so­called Hurricane Bawbag in Scotland in 2011. But it led to confusion (混乱)," a Met Office spokeswoman said.

    According to the Met Office, there is a name for each letter of the whole alphabet (字母表), except for Q, U, X, Y and Z. That is the same as the naming tradition used in America. And not all storms will be big enough to get names — only those expected to cause great damage.

    If there are more than 21 storms in a year, the Met Office will start again with another name beginning with "A". However, according to Met Office spokeswoman Lindsay Mears, "It's unlikely we would get through the whole alphabet in one season. We had 14 storms in the very bad winter of 2013/14, and if the naming system had been in operation then we wouldn't have used the whole alphabet."

    Memory, they say, is a matter of practice and exercise. If you have the wish and really make a conscious(自觉的) effort, then you can quite easily improve your ability to remember things. But even if you are successful, there are times when your memory seems to play tricks on you.

    Sometimes you remember things that really did not happen. One morning last week, for example, I got up and found that I had left the front door unlocked all night, yet I clearly remember locking it carefully the night before.

    Memory "tricks" work the other way as well. Once in a while you remember not doing something, and then find out that you did. One day last month, for example, I was sitting in a barber shop waiting for my turn to get a haircut, and suddenly I realized that I had got a haircut two days before at the barber shop across the street from my office.

    We always seem to find something funny and amusing in incidents caused by people's forgetfulness or absent-mindedness. Stories about absent-minded professors have been told for years, and we never get tired of hearing new ones. Unfortunately, however, absent-mindedness is not always funny. There are times when "tricks" of our memory can cause us great trouble.