The Internet has opened up a whole new online world for us to meet, chat and go where we've never been before.

    But just as in face to face communication, there are some rules of behavior that should be followed when on line. {#blank#}1{#/blank#} Imagine how you'd feel if you were in the other person's shoes.

    For anything you're about to send: ask yourself, “Would I say this to the person's face? If the answer is no, rewrite and reread. {#blank#}2{#/blank#}

    If someone in the chat room is rude to you, your instinct (本能 ) is to fire back in the same manner. But try not to do so. {#blank#}3{#/blank#} If it was caused by a disagreement with another member, try to fix the situation by politely discussing it. Remember to respect opinions of others in the chat room.

    {#blank#}4{#/blank#} Offer advice when asked by newcomers, as they may not be sure what to do or how to communicate. When someone makes a mistake, whether it's a stupid question or an unnecessarily long answer, be kind about it. If it is a small mistake, you may not need to say anything. Having good manners yourself doesn't give you license to correct everyone else. {#blank#}5{#/blank#} At the same time, if you find you are wrong, be sure to correct yourself and apologize to those you have offended.

A. The benefits of visiting museums

B. Educational functions

C. Places for collections of objects

D. The history of museums

E. Precious chance to see famous masterpieces

F. Ways to improve their collections

    {#blank#}1{#/blank#} Museums are places where collections of objects are preserved and put on show. The objects may be anything found in nature made by man. There are museums devoted to art, science, history, industry and technology.

    {#blank#}2{#/blank#} But museums are no longer just storehouse for collections. Today nearly all museums, large or small, carry on educational programs. Museums offer guided tours, lectures, films, music recitals, art lessons, and other attractions. They organize field trips and clubs. They publish guides to help visitors to gain a better understanding of the collections.

    {#blank#}3{#/blank#} All museums share a common aim —— to attract visitors and help them to understand and enjoy the collections. Museums are always on the watch for new additions to their collections. Works of art are bought from art dealers and private collectors. Museums also accept gifts, but the large museums no longer accept everything that is offered to them. They accept only objects of collections that meet their high standards.

    {#blank#}4{#/blank#} Museums often arrange loan exhibitions of important works from private owners, art dealers and other museums. In this way a famous masterpiece may be viewed by people who otherwise might never have the chance to see it. For example, in 1963 the Metropolitan Museums of Art in New York city exhibited one of the world's most famous ladies —— Mona Lisa, painted by Leonardo Da Vinci. The government of France had lent the painting to the United States. Attendance at the Metropolitan reached an all-time high during the month Mona Lisa was shown there.

    {#blank#}5{#/blank#} What is to be gained from visiting museums? Museum exhibits can teach us about the world in which we live —— the materials it is made of, the trees and plants that cover it, and the animals that have lived on it since its beginning. We can learn about the activities of man —— his history and development as well as his accomplishments in arts and crafts. Most people see a great work of art for the first time in a museum. We cannot all be explorers or collectors in other lands. But in a museum we can see for ourselves the objects that have been gathered from every part of the world.

    Wondering where to watch the fireworks on the fourth Friday of July? Here are some restaurants where you can sit, grab a bite to eat and watch the show.

    The Roof on Wilshire offers a view of the city, so chances are that you'll be able to catch a fireworks show while you're up there. The restaurant will also offer an all-you-can-eat menu for $20 that includes all beef hot dogs and sweet potato chips. The festivities will take place from 2 to 11 pm. Reservations are recommended. 6317 Wilshire Blvd. Los Angeles, (323) 852-6002.

    Whiskey Red's is located in Marina Del Rey. Beginning at 5:30 pm, it will include live music from Jack of Hearts. The event is free and open to the public. Guests can make reservations from 5:30 to 10 pm. It costs $59 to reserve a seat on the patio(露台) and $49 for indoor seating. Kids aged 5 to 12 need $25 for a seat outside and $20 for an indoor seat. Kids aged four and below are free. 13813 Fiji Way, Marina Del Rey, (310) 823-4522.

    High Rooftop lounge in Venice at the top of the Hotel Erwin offers views of the Venice coastline. The fireworks show starts at 9 pm. The rooftop lounge (休息室) offers a full menu of cocktails and a selection of snacks. 1697 Pacific Avenue, Venice Beach, (800) 786-7789.

    The last one is Carbon Beach Club at the Malibu Inn. Here you can see fireworks from a seat on the restaurant's oceanfront balcony from 6 to 9:30 pm. Reservations are recommended. 22878 Pacific Coast Hwy, Malibu, (310) 456-6444.

    To save as much language diversity as possible in the face of its rapidly dying out, researchers suggest using “evolutionary trees”, a tool from conservation biology.

    One of the world's 7,000 languages disappears every other week, and half might not survive the 21st century, experts say.

    When setting conservation goals, ecologists use evolutionary trees—diagrams that show how biological species are related to one another—to identify species that have few close relatives. Such species are said to be evolutionarily distinct. Similarly, recent advances in the construction of language trees make it possible to measure how unique a language is.

    “Evolutionary trees have transformed our understanding of how life has evolved and helped us to decide which species most need conserving,” says Jonathan Davies, senior author of the new study.

    “The rapid rate of language loss, as well as limited resources for preservation（保护）, means that we must choose carefully where to focus our efforts,” adds Max Farrell, a PhD student in Davies' lab. “The more isolated (孤立的) a language in its family tree, the more unique information it contains and eventually contributes to language diversity.”

    As a case study, they used this approach to rank 350 Austronesian languages, spoken in islands spread across Southeast Asia and the Pacific Ocean.

    For each of these languages, the researchers combined measures of evolutionary distinctiveness (ED) and global endangerment (GE) to produce an “EDGE” score. The language with the highest score, which means it is extremely distinct（不同的） yet nearly dying out, was Kavalan, a language native to Tai Wan. The next-highest scores went to Tanibili, an endangered language in the Solomon Islands.

    By building trees for other language groups, language specialists could target preservation efforts and help reduce the loss of language diversity in the future, the researchers say.

    A research project jointly carried out by scientists from several British universities and institutes has drawn people's attention to the toothbrush again.

    Researchers have found that your toothbrush is home to more than 100 million bacteria. But there are hundreds of microorganisms in the mouths and your toothbrush probably won't make you sick unless there is an unhealthy balance of bacteria. Our immune system can usually take care of bacterial invaders. However, if others use your toothbrush, or you use someone else's, bacteria can be spread.

    They have also found the toothbrush holders are the third-most dirty household items (behind dish sponges and kitchen sinks), thus advocating cleaning the toothbrush holder regularly.

    The storage of your toothbrush in your bathroom is also important. Here are some storage tips from the researchers to keep your toothbrush as healthy as possible:

    Put your toothbrush as far away as possible from the toilet flushing.

    Let your toothbrush dry thoroughly between brushings.

    Don't use toothbrush covers, which can create a perfect breeding ground for bacteria.

    Keep your toothbrush upright in a holder rather than lying down.

    Keep toothbrushes separate. If toothbrushes touch, they can exchange and spread bacteria.

    There are products available that claim to sanitize（消毒）your toothbrush. While some of these products do kill some bacteria, there is no evidence that using them will reduce your risk of illness, according to the researchers.

    They recommend replacing your toothbrush every three to four months or more often if you are sick or if you have a weakened immune system. Children's toothbrushes may need to be replaced more often than adult brushes.

    Standing in line for the latest iPhone at the Apple store  queuing for tickets to the match or even just waiting at the post office might just have got a lot easier.

Japanese car-maker Nissan announces that it has just the thing to relieve the painful legs of tired queuers.

    The new system of self-driving chairs is designed to detect when someone at the front of the queue is called, and automatically move everyone else one step forward in line.

    The new invention is shown in a company video, which shows a busy restaurant with customers waiting outside. In the video, diners are sitting in a row of chairs, but will not have to stand when the next hungry diner is called to a table. Instead, the chairs, equipped with autonomous technology that detects the seat ahead, move along a path toward the front of the line. When the person at the front of the queue is called, the empty chair at the front can sense it is empty and so moves out of line. Cameras on the remaining chairs then sense the movement and follow automatically.

    “The system, which is similar to the kind used in Nissan's autonomous vehicle technology, will be tested at select restaurants in Japan this year," Nissan said. "It appeals to anyone who has queued for hours outside a crowded restaurant: it rids the boredom and physical pain of standing in line,” Nissan added.

    Although Tokyo has some 160,000 restaurants, long queues are not uncommon. Chosen restaurants that meet the criteria will be able to show the chairs outside their restaurants next year. Nissan also released a short video showing the chairs being used in an art gallery, moving slowly in front of the various paintings to let viewers appreciate the art without the need to stand up.