While watching movies, it's getting hard to tell what is and isn't real. Thanks to computers, movie makers can now use their full imaginations. There's even a new type of character--made entirely by computers—which is getting more and more screen time.
    Making the impossible look easy has always been a part of movie magic. As far back as 1895, filmmakers used special effects in movies. Over the years, many few techniques（技术） were developed. Then, starting in the 1970s, computers took their place at the center of the process.
    One of the first movies to widely use 3D computer generated（生成的，产生的） imagery (CGI) was Tron(1982). In the following years, more CGI characters were brought to life, one by one. Then, Jurassic park (1993) brought us an island full of man-eating dinosaurs. Shortly afterwards, Toy Story (1995) became the first cartoon made entirely with 3D CGI effects. It was a big hit, and audiences loved the characters.
    By using “motion capture” technology, filmmakers can make the movements of CGI humans even more lifelike. With this technique, a real actor wears sensors（感受器，传感器） on his face and body. The sensors record the actor's movements and send the information to a computer. Then the movements are given to a CGI character. This technique was used to make the creature（生物，有生命的东西） Gollum in the second and third The Lord of the Rings movies (2002, 2003). Other films, like Beowulf (2007), have also used motion capture to help create CGI humans.
    It is still rather easy to tell that a CGI human is not real. But the technology is improving every year. Over time, many problems ( like the teeth and eyes looking fake) will be solved. We will certainly see more CGI animals, monsters, and people in movies and TV shows. The question is – in the future, how many real actors will be put out of work by computer actors?

    A city without cars would be very strange, right? But Venice is such a city.

    Venice is in the northeast of Italy. It wasn't built on land, like Beijing or Shanghai, but on more than 110 islands. Seawater is everywhere around the city.

    Even so, travel isn't difficult. The waterways have always been the best way to get around. There are 117 waterways and more than 400 bridges that can guide you where you want to go.  People in Venice move from place to place by boat.

    Water makes the city special, but it is also a big problem. Sometimes tourists will have such strange experiences. One moment they walk across the Rialto Bridge, and there's nothing special. But when they come back to the bridge an hour later, it's underwater and everyone is wearing rain shoes.

    Once, people used too much underground water. This made the city get lower little by little. Now the city has gone down by 23 centimeters. Another problem is the rising seawater. The temperature has risen over the years. This has made the ice of the Arctic Ocean (北冰洋) melt( 融化). Every year, high waters hit the city in autumn and winter. When a lot of water comes, more than half of the city is underwater.

    Scientists are trying different ways to stop the city from getting even lower. The Italian government has asked some of Italy's biggest companies to build the MOST project, which was planned to be build under the seawater to stop the rising water. Anyway, this project is helping solve the problem.

    Radios, telephones and televisions are widely used in the world. When you switch on the radio, you can listen. But when you use the telephone, not only can you listen to others, but also you can chat with them. However, you cannot see anything at all. Television is much better than both of them. People can watch TV and listen to it, but they cannot take part in what they see.

    Today, some people are using a new type of telephone called vision phone. With it two people who are talking can see each other. Vision phones can be of great use when you have something to show the person whom you are calling. It may also have other uses in the future. Some day you may be able to call up a library and ask to read a book right over your vision phone. You may be able to do the shopping through it too. Perhaps in the near future, vision phones will come into our everyday life.

    There are all kinds of animals on our planet. Some are sweet, but some are not; some are small, and some are tall. Here are four pictures of some of the funniest, friendliest faces. But remember, although they look nice, it doesn't mean they are always friendly.

    Not all dogs are so cute, but most of them are pretty friendly. When you come near an unfamiliar(不熟悉的) dog, remember to hold out your hand, so he can smell you and see that you mean no harm.

    Cows love to eat grass, and they eat quite a lot! You needn't be afraid of this quiet farm animal. But don't run at a cow in a field or touch one, unless you are told by an adult it's okay.

    Horses are big, beautiful animals, but they can be easily angry. A horse might jump up if she hears a loud noise, or kick her legs if you come near too suddenly. All horses, like humans, are different.

    Chimpanzees(黑猩猩) make funny faces and put on a real show at the zoo, but believe it or not, they can be very dangerous. And they are strong too--much stronger than humans--so you should never make a chimp mad!

    One day, you open the fridge and find some moldy (发霉的)food. But before you can throw it away, your mother stops you. She doesn't want to waste food. She cuts off the moldy part and eats the rest. Is it safe to do this?

    Mold (霉菌)can grow on almost all kinds of food. Mold is usually green, white, black or grey. Mold makes food soft and changes its color. Moldy food tastes quite bad一一and it's not safe to eat.

    If you find mold in soft food, just throw it away. Soft food, such as bread, tomatoes or hot dogs, usually contains water. This allows mold to easily grow below its surface. Bacteria (细菌)can also grow along with it.

    But it's easy to remove mold from hard food. The mold can't grow very deeply inside this kind of food. According to the BBC, you should cut about 2.5 cm around and below the mold to remove it. It's OK to cut the moldy parts out of hard food and eat the rest. But if the food is completely covered with mold, you should still throw it away.

    Most kinds of mold are bad for us. But some kinds of mold can be used to make food. For example, penicillium (青霉菌)can be used to make many types of cheeses, such as blue cheese. These cheeses are safe to eat--and they're quite delicious as well.