Social change is more likely to occur in societies where there is a mixture of different kinds of people than in societies where people are similar in many ways. The simple reason for this is that there are more different ways of looking at things present in the first kind of society. There are more ideas, more disagreements in interest, and more groups and organizations with different beliefs. In addition, there is usually a greater worldly interest and greater tolerance in mixed societies. All these factors tend to promote social change by opening more areas of life to decision. In a society where people are quite similar in many ways, there are fewer occasions for people to see the need or the opportunity for change because everything seems to be the same. And although conditions may not be satisfactory, they are at least conventional and generally agreed.

    Within a society, social change is also likely to occur more frequently and more readily in the material aspects of the culture than in the non-material, for example, in technology rather than in values; in what has been learned later in life rather than what was learned early; in the less basic and less emotional aspects of society-than in their opposites; in the simple elements rather than in the complex ones; in form rather than in substance; and in elements that are acceptable to the culture rather than in strange elements.

    Furthermore, social change is easier if it is gradual. This is one reason why change has not come more quickly to Black Americans as compared to other American minorities, because of the sharp difference in appearance between them and white people.

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    You dash through a crowded railway station, tripping over bags, spilling (泼出) your coffee, only to have the doors slide shut in your face, leaving you breathless on the platform as the train pulls away,

    But at least, if you're in France, someone may be playing the piano for you. But it won't be performed by a paid musician, or even a street entertainer playing for coins. It will just be a random passer - by, jamming for the fun of it on one of the pianos that the national railroad company, S. N. C. F., has fixed in nearly 100 stations across France. They are free for anyone to play, and travelers from all walks of life have taken to doing just that.

    Gares & Connexions, the S. N. C. F. division that manages its stations, rents the instruments from the producer, Yamaha: which maintains them and tunes them every month or two. The first one was set up in the Gare Montparnasse in Paris in 2012.

    The music, mixed with the sounds of shouting passengers, screaming trains and rolling suitcases, gives French stations a special soundscape. The amateur musicians have included Irish soccer fans and even babies. In 2014, Gares & Connexions and Yamaha organized a nationwide contest called Your Turn to Play, asking participants to submit videos of themselves using one of the pianos. It drew nearly 900 entries.

    Isn't the railroad company taking a big chance? Apparently not: “None of the instruments has been vandalized to this day, or even merely damaged,” said Claire Foumon, a spokeswoman for Gares & Connexions. “They are shared and respected by all.”

    So if you miss a train in Paris; Bordeaux or Marseille one day, perhaps someone will be playing a favorite piece that will ease your pain. Or perhaps you'll sit down and play your annoyance away yourself.

    A five-year-old dog named Kelsey has been praised as a hero for helping to save the life of her owner who slipped in the snow and broke his neck.

The man, Bob, was alone when he left his Michigan farmhouse on New Year's Eve to collect firewood. Expecting a journey of only several meters, Bob was wearing just long johns(衬裤), a shirt and slippers when he went outside, although the temperature was around-4℃.

    After the accident, he was unable to move in the snow. Fortunately, Kelsey came to his assistance.

    "I was shouting for help, but my nearest neighbor is about 400 meters away, and it was10:30 pm," Bob explained. "But my Kelsey came. By the next morning, my voice was gone and I couldn't yell for help, but Kelsey didn't stop barking."

    Kelsey's companion kept him warm by lying on top of him. She licked his face and hands to keep him awake. "Kelsey kept barking but never left my side," Bob recalled. "She kept me warm. I knew I couldn't give up and that it was my choice to stay alive."

Bob spent 20 hours in the freezing cold. When he finally lost consciousness, his dog kept barking. Finally, hearing the barking, Bob's neighbor discovered him at 6:30 pm on New Year's Day and called the emergency services at once. When Bob arrived in hospital, his body temperature was below 21℃. However, doctors were surprised to find that he didn't have any frostbite(冻疮). They believed it was because of Kelsey's determination to keep him warm. Dr. Chaim Colen, the doctor who treated Bob, said, "Animals can help and his dog really saved him... He was very fortunate.

    Bob said he was "enormously" grateful to both Dr. Colen and his Kelsey. "They saved my life. They are truly heroes!"

    The Winter Olympics is also called the White Olympics. At this time, many colorful stamps are published to mark the great Games. The first stamps marking the opening came out on January 25, 1932 in the United States for the 3rd White Olympics. From then on, publishing stamps during the White Olympics became a rule.

    During the 4th Winter Olympic Games a group of stamps were published in Germany in November 1936. The five rings of Olympics were drawn on the front of the sportswear. It was the first time that the rings appeared on the stamps of the White Olympics.

    In the 1950's, the stamps of this kind became more colorful. When the White Olympics came, the host countries(东道国)as well as the non-host countries published stamps to mark those Games.

    China also published four stamps in February 1980, when the Chinese sports men began to take part in the White Olympics. Japan is the only Asian country that has ever held the White Olympics. Altogether 14,500 million stamps were sold to raise money for this sports meet. Different kinds of sports were drawn on these small stamps. People can enjoy the beauty of the wonderful movements of some sportsmen.

Father's Day is celebrated today in 75 countries around the world. In my personal world, it's a day I like to think of my father's father.

I learned a lot in my later life from my dad. But I learned something else, as a kid not even yet in school, from my grandfather. I learned to be curious. Little things fathers and grandfathers do can change the life of a child forever. In my case, this change came from necessity：My mom needed someone to look after little Allen, barely 4 years old, during the school day. My grandmother volunteered, and my grandfather came up with a way I could be watched while he worked in his clockmaker's shop.

He seated me on a chair every day while I was there, right in front of his big workbench.  He told me stories. He had a great sense of humor and a funny way of making a "buh﹣buh﹣buh" sound when he sensed my attention was weakening, and he encouraged me to ask questions about anything he was doing.

Naturally, I was usually asking questions about clocks﹣what made the hands move, what the pendulum (钟摆) did, why you had to stop winding just before the weight hit the stop.  Sometimes I just asked about which shiny parts went where.

Most of all, he showed me how clocks worked. He treated me as if I were a sort of small grown﹣up. He never talked down to me, never told me I was "too young to understand".

And so my grandfather granted me two things: A love of clocks, and an everlasting curiosity.

As a journalist, I turned that fascination into explanations of why computers and software do what they do﹣﹣and, perhaps even more importantly, why they fail at that task. I haven't been afraid of opening up the innards and looking for what is wrong with the computer.

Do you have plastic bottles at home？Did you throw empty plastic bottles into the trash，just because you didn't know how to use them？However，there are many interesting things you can do with empty plastic bottles! {#blank#}1{#/blank#}

● Spray for your garden. {#blank#}2{#/blank#} Then adjust the rubber bracelet to the mouth of the bottle，and make sure the plastic bottle mouth neatly fits through the hole in the lid.When everything is ready，you will have a spray bottle for your garden! 

● Separate eggs.Do you find it challenging to separate eggs？In some recipes，you just need the yolks （蛋黄） or the whites，but the process is a bit complicated. {#blank#}3{#/blank#} Break the egg into a bowl.Remove the lid from the bottle and pinch a little.Then continue the pressure，put the ends into the yolks and stop the pressure.In this way，the yolks will be absorbed into the bottle while the whites will remain on the plate. 

{#blank#}4{#/blank#} When making biscuits，you may need tools to cut them.Plastic bottles will do again.Making a homemade biscuit cutter from plastic bottles is the best way to reuse plastic bottles，as you never know the situation when you need to use it.You just need a small or a large plastic bottle depending on your needs. {#blank#}5{#/blank#} And then take one of two sections to cut the biscuits. 

A.Cut off the biscuits. 

B.Make biscuits easily. 

C.Cut the bottle into half. 

D.So next time take advantage of them. 

E.Use bottles to kill garden pests effectively. 

F.Don't worry，and you can solve this problem with a plastic bottle. 

G.For this trick，you only need to drill a few holes in a plastic bottle.