Have you ever wondered why people drive on a different side of the road? It might seem bizarre that U. K. drivers stay on the left, but they're not the only ones. Around 35 percent of the world population do the same, including people in Ireland, Japan, and some Caribbean islands.

    Originally, almost everybody traveled on the left side of the road. However their way of transport was quite different from today: Think about four legs instead of four wheels. For Medieval swordsmen on horseback, it made sense to keep to the left to have their right arms closer to their enemies. Getting on or off was also easier from the left side of the horse, and safer done by the side of the road than in the center.

    So why did people stop traveling on the left? Things changed in the late 1700s when large wagons (货车) pulled by several pairs of horses were used to transport farm products in France and the United States. The wagon driver sat behind the left horse, with his right arm free to use his whip to keep the horses moving. Since he was sitting on the left position, he wanted other wagons to pass on his left, so he kept to the right side of the road.

    The British Government refused to give up their left-hand driving ways, and in 1773 introduced the General Highways Act, which encouraged driving on the left. This was later made law thanks to The Highway Act of 1835.

    When Henry Ford showed his Model T in 1908, the driver's seat was on the left, meaning that cars would have to drive on the right hand side of the road to allow front and back passengers to exit the car onto the roadside. However, British drivers remain on the left, and this is highly unlikely to change.

    Home gardening is an enjoyable family activity. It brings many benefits to your body's health, your wallet and the environment. There is the fun of growing whatever pleases you all year round. And you can get the freshest and safest vegetables.

    However, being a home gardener in modern society is tricky. As you have too much to do every day and have no time to take good care of them, all your plants may die. Luckily, there are many gardening apps that are helpful in teaching the art of growing a wonderful garden.

    One of them is Gardenia. It can provide a great deal of information for crazy gradeners who want to increase their gardening skills and continue growing fresh produce. If you've got a smart phone with this app, everything becomes a lot easier, whether you are a beginner or an expert in home gardening.

    Gardenia is designed to teach you the best gardening tips, and it can predict how fast the plants much have grown and what needs to be done. It is light with a beautiful interface (界面), user - friendly and easy to use. Anyway, Gardenia is a perfect planting organizer for you to use and plan your green tasks. It was developed by an experienced home gardener.

    The best thing about this app is its over 90,000 different plants library for you to choose and the right way of planting each of them. More importantly, it helps everyone recognize a plant that grows well in their local area. So it's always something you deserve to enjoy! Do use it on your phone if you're really interested in gardening.

    You're sitting on the sofa, and there's your dog, right at your feet. You stand up? He stands up. But then you head to the bathroom, and guess who comes with? Why, your dog, of course. But why? Why does your dog follow you like a shadow, no matter where you go?

    Ever get the feeling you're being followed? As for why your companion follows you everywhere you go, read on!

    "When dogs follow their owners, there can be several scientific explanations, depending on the dog and the individual situation," according to Mary Burch, Ph.D., an animal behaviorist(行为学家).

    These explanations include:

    Positive reinforcement(正面强化): When your dog follows you, good things happen. Think dog food, a hot bath and taking a walk around the neighborhood. Your dog's no dummy. And one of his many talents is learning from experience, that is "reinforcement."

    Natural instinct(本能) to be part of a pack: In fact, a study out of Princeton University that was published in the journal, Science Advances, shows that your dog's drive (驱动力)to follow you around (as well as watch you attentively and seek physical contact (身体接触) from you) lies in his genes(基因).

    Feel good chemicals(化学物质): Your presence causes your dog's brain to release "feel good" chemicals, Dr. Primm explains, citing this study. Considering how much we as humans enjoy those feel-good chemicals, it's no surprise your dog likes them too—and will follow you around to get some!

    Sense of responsibility : As you move about your home, your dog might feel that you are patrolling your territory (巡视领地) and take on the duty to assist you.

    Spring is a wonderful season to celebrate rebirth and new life. The long, cold winter is over. The weather is warmer and sunnier. The trees again have leaves and the flowers are blooming. The season represents hope, joy and beauty. At this time, many people think of this classical music piece—Spring, which shows happiness. Italian composer Antonio Vivaldi wrote it in the seventeen hundreds.

    However, not all songs about spring are happy. This song written and sung by K.D. Lang is about dreaming of spring in cold dark places. She recorded I Dream of Spring in 2008.

    Richard Rodgers and Oscar Hammerstein wrote It Might as Well Be Spring for the movie State Fair in 1945.Frank Sinatra sings it. It is a feeling of restlessness or excitement brought on by the coming of spring. Richard Rodgers also wrote Spring Is Here, this time with Lorenz Hart. Ella Fitzgerald sings this song about feeling lonely during this season.

    Frank Loesser wrote the sad song, Spring Will Be a Little Late This Year. Why has the season been delayed? Because the singer's lover has left her. Sarah Vaughn released(发行) her version of the song in 1953.

    By now you may be thinking, "Enough with the sad songs, already！"OK ,then how about a cowboy song? Gene Autry was one of the America's most famous singing cowboys. He recorded When It's Spring time in the Rockies in 1937.

    And finally, we'll leave you with a sunny song called Up Jumped Spring. Freddie Hubbard wrote this jazz song in 1977 and Billy Taylor Trio performs it.

    One of the most important things in the world is friendship. In order to have friends, you have to be a friend. But how can you be a good friend at school？

Listen﹣Listen when they are talking. Don't say anything unless they ask you a question. Sometimes it's not necessary for you to have anything to say; they just need someone to talk to about their feelings.

    Help them﹣If your friend is ever in need of something, be there to help them. You should try to put them first, but make sure you don't do everything they want you to do. Try to take an extra pencil or pen with you to classes in case they forget one. Have a little extra money in your pocket in case they forget something they need.

    Be there for them﹣Be there for your friends to help make them feel better in hard times. Marilyn Monroe, a famous U.S. actor, once said, "I often make mistakes. Sometimes I am out of control, but if you can't stay with me at my worst, you are sure not to deserve to be with me at my best." Always remember this! If you don't want to stay with your friends when they're in hard times, then you don't deserve to be with them when they're having a good time!

    Make plans﹣Try to make plans with your friends. Go shopping, go for ice cream, have a party, go to a movie and so on. Take time to know each other even better by doing something you both enjoy. By planning things together, you both can have a good time. And you'll remember these things when you're all old!

With the summer heat becoming increasingly unbearable over the years due to climate change,the cooling load in the summertime has also been on the rise.Insulation(隔热) is currently the main solution for blocking heat from entering a building,but by applying an additional material that can delay heat penetration(渗透),it can prevent the indoor temperature from rising and in turn lower the cooling load of the building.

A research team in Korea has developed a new material for building walls that can help reduce the penetration of heat from the outside.The team directed by Dr.Sarng Woo Karng from KIST revealed that they have successfully done it through building walls by applying a phase change material(PCM).One of the most common types is paraffin oil,which is used to make candles.

A solid PCM absorbs heat as it transforms into a liquid phase,so by using a case to hold it when it is in a liquid phase without causing any leakage(渗漏),it is possible to apply them to a building wall to block heat from entering inside.

The problem,however,is that the PCM turns into liquid starting from the outermost layer,and the parts that are hot move upward,while the parts that are still relatively cool move downward.Thus,while the upper part may have completely melted,the lower part will have not,and as a result,heat will penetrate into the building through the area where the PCM is in a liquid phase.In the end,the PCM becomes ineffective in controlling the indoor temperature and is rendered useless.

Dr.Karng's team addressed the non-uniform phase change with bubble injections.Injecting bubbles into the bottom part of the PCM enabled uniform circulation(流动)of the PCM in a liquid phase.Dr.Karng said,"We expect that the insulating wall using the PCM bubble generator used in this study will contribute to reducing the amount of energy used to heat or cool a building.Insulation techniques using the PCM help reduce heat penetration,in combination with the building insulating material,and it can also be used as the outer walls of zero-energy buildings."