I used to believe courtesy(礼貌) was a thing of the past. Very seldom have I encountered a courteous human being in this modem era of the so called Generation X.

    Recently, I had to change my thinking, when I came face to face with just such a human being. I had gone to a happening coffee place, with two of my grown up daughters. The place was crowded with the usual loud crowd and we had to climb a sleep flight of stairs in order to find an empty table. After enjoying coffee and snacks, we were at the steep descent down the stairs, where the narrow space made climbing down only possible in a single file, with hardly any space for another person to either climb up or come down.

    Just as I was in the middle of my descent, a gentleman entered the main entrance of the restaurant which right in front of the staircase. I was sure I would be pushed roughly by this man who will want to go up in a hurry. I kept coming down as fast as I could, holding on to the banister (栏杆), instead of my advanced years. My agile daughters were already down, looking up at me worriedly, hoping I would reach them before the stranger strange started up the stairs, knowing I was a nervous sort.

    Nearly reaching them, I noticed the man still standing near the door. I reached my daughters and passed the stranger at the entrance door which he kept holding open. I looked back thinking he was still at the door, deciding whether to go in or find another less crowded place. I saw him going up the stairs, two at a time. I told my daughters about it and all three of us felt had that we did not even thank the courteous gentleman who was actually holding the door open for us ladies to pass through before going up.

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    As I enter my 40s, I've noticed many of my parents' generation think social networking is something they are simply unable to understand. They fear that, should they try, they will somehow get it wrong; they will say the wrong thing, do the wrong thing or behave in a way that causes embarrassment(尴尬). But here's the first secret of social media: Everyone feels this way.

    I recently met a young actor who was complaining that her work demands that she join Microblog, but she always feels like she doesn't have anything smart to say. It's the same resistance (抵制)I hear from the older generation, who, however, have somehow believed that age is the barrier(障碍), rather than the differences of personal taste.

    Here's the second secret of social media: everybody uses it for more or less the same reasons. Older generations often sign up to stay in touch with children and relatives. We talk about this kind of communication like it's some old-fashioned activity, but it is exactly why younger people use social media. The truth is that most people use social media to gently keep an eye on one another, to see how those they care about are doing without needing to ring them up on the phone every night.

    And this is the last secret of social media: everyone gets to use them in their own way. Newcomers—younger and older—who worry about “getting it right” are thinking that there's a right way to get them. But actually there isn't. Personally, I talk a lot on Microblog. And some people post nothing and they use social media every day as readers. Social media companies would rather see people decorating their networks with pictures and posts, but there's no rule against being a fly on the wall. It's also a fine way to get involved.

    We're quick to forget that the web wasn't invented by 13-year-olds; it was created by today's seniors. I'd never try forcing those with no interest in social networks to use Microblog. But don't let the talk of age divides put you off. There's nothing to stop the older generation from joining in the network their own generation created.

    April 4th was just another day on a Western Australia farm for Zac Mitchell, until it suddenly wasn't. In an unexpected accident, the cattle worker was feeding the animals in his charge when one bull cleaned him up and kicked his hand up against the rail, resulting in the thumb on his right hand being cut off. “My thumb was still hanging on the rail... when I got up off the ground,” Zac Mitchell says.

    His co-workers tried their best to preserve the thumb for reattachment, placing it on ice in a cooler, but two surgeries to put Mitchell's thumb back in place failed. That's when doctors came up with another suggestion: Remove one of his big toes to where his thumb used to be.

    Mitchell's lead surgeon, Sean Nicklin, understood the man's dilemma at first, calling it a “bit of a crazy idea”. After all, Zac Mitchell did not want to be injured in another part of his body. But as the thumb is incredibly important function-wise, Mitchell eventually gave in. Nicklin explains that the big toe is surprisingly fit for a thumb switch: Nerves sync up (同步) nicely, and it looks more like a thumb, though a giant one, than any other alternative they may have come up with. He added that big toes aren't as necessary for balance and walking as people believe. As far as the foot goes, occasional “fine balance” activities like surfing might be difficult, but most people without a big toe function fine in everyday tasks like walking and even competitive sports.

    The eight-hour surgery went well, and Mitchell is expected to have a year or so of recovery in front of him before he heads back into the fields.

    STA Travel, the world's largest students and youth travel agency, beats any price! Every day we're working with our partners around the globe to get you (students, teachers and anyone under 26) the cheapest and most comfortable flights and top-rated accommodations. This part of www.statravel.com provides great tips for green travel — how to pack, how to leave your house or apartment, and how to plan for your trips. You'll also find a great selection of green travel adventure trips to all corners of the world.

    Green travel means responsible (负责任的) travel! Leave as little influence as possible on the places you visit and protect the environment both at home and during your trip. Think “Green” when you pack and when you travel. You'll help prevent long-term effects on the communities you leave and visit! Here's some advice on how to do that.

    Before you leave

    Turn your water heater to its lowest setting.

    Turn off your water from the outside.

    While you travel

    Pack suitable clothes in your luggage, none of which is to harm the environment.

    Try products made from recycled materials.

    Don't buy souvenirs produced from endangered species.

    Carry a reusable bottle for water and refill it as you go.

    Use the bathroom in the airport, NOT on the plane. The fuel used for a single flush (冲洗) could run a car for six miles.

    Newspapers in Great Britain vary greatly in their ways of carrying the news. There are serious papers for those who want to know about important happenings everywhere, both at home and abroad. There are popular newspapers for those who prefer entertainment to information.

    The London newspaper that is best known outside Great Britain is probably the Times. It began in 1785, and has a high reputation for believable news and serious opinions on the news. It calls itself an independent paper, which means that it does not give its support to a particular political party. Its leading articles give the opinions of the editors, not those of the owners of the paper.

    Letters to the editor are printed in the newspaper. These parts of the Times are always interesting. Most of the letters are serious subjects. But from time to time there will be long letters on the subject which is not at all serious, perhaps on a new fashion of dress, or the bad manners of the young people, compared with manners of thirty years ago.

    I was asked by a reader recently why so many animals seem to have pink ears, when their bodies are all different colours? The truth is that most animals actually don't have pink ears. Let us explain.

    Near the equator (赤道), where the climate is hot, animals are likely to have darker skin, including on their ears. Think of the African elephant, which has quite dark ears. In colder climates, skin colour is usually lighter and often pink.

    Why is skin colour different in different climates？Skin pigmentation, which is what gives skin its colour, can protect against sunburn and skin cancer (癌症). When animals live in colder parts of the world, they don't need it as much to survive. Light-coloured skin also helps animals stay warmer because it reduces heat loss, which is useful if you're in a colder climate.

    For most animals, the colour of their fur or other body covering has generally developed as camouflage. That allows animals to mix into the background and avoid being eaten, or for predators (捕食者) to remain hidden during hunting. One example is the sandy-coloured coat of the desert fennec fox, which uses camouflage for both hunting and hiding.

    By the way, in many animals, ears come in many different shapes and sizes. For example, in bats, the serval (a type of African wildcat) and the fennec fox, the ears are large compared to their body size—this helps them hear better because it allows them to sense more sound waves. Naked mole-rats have tiny ears because they need to dig a lot. Big ears would get in the way. The other downside of big ears is that you can lose a lot of body heat. That's why animals that live in really cold places, like the Arctic fox, have quite small ears.