Last year，I was on a plane with my friend, waiting for it to take off．The pilot's voice was heard throughout the plane “Sorry for the delay, ladies and gentlemen. Our engines don't work．We are going to jump-start them．Once we get them going, we'll get up in the air and see what happens．"

    That was all he said．"See what happens. Shouldn't we have had a better plan than that？"At that point, I could only laugh nervously. One woman started crying, “OH，no! We are going to crash!”. There are signs of desperation and anxiety, and we hadn't even taken off yet．

    The pilot even seemed unhappy．He told us one engine was working double time and his plan was to get up in the air and see what happens! Then we did．We got up in the air，and what happened？

    Nothing．We arrived in Norfolk, and no sooner had the wheels touched down than applause burst out as everyone on the airplane breathed a sigh of relief．

    All too often, people stop achieving their goals just because they don't have a guaranteed result．But success will never be guaranteed. The best thing that you can do is to just get up in the air and see what happens．

    If your aim is to build a business, then get up in the air and see what happens! Don't give yourself all the reasons why you can't．Do not wait until you have everything you need．You never will．

    If your goal is to start a friendship，say"Hello",get up in the air and see what happens! The results could be very rewarding．If your goal is to learn a new skill, get up in the air and see what happens! It might not be as difficult as you think．It could be fun!

    There's a new frontier in 3D printing that's beginning to come into focus: food. Recent development has made possible machines that print, cook, and serve foods on a mass scale. And the industry isn't stopping there.

    Food production

With a 3D printer, a cook can print complicated chocolate sculptures and beautiful pieces for decoration on a wedding cake. Not everybody can do that—it takes years of experience, but a printer makes it easy. A restaurant in Spain uses a Foodini to" re-create forms and pieces" of food that are" exactly the same,” freeing cooks to complete other tasks. In another restaurant, all of the dishes and desserts it serves are 3D-printed, rather than farm to table.

    Sustainability(可持续性)

    The global population is expected to grow to 9.6 billion by 2050, and some analysts estimate that food production will need to be raised by 50 percent to maintain current levels. Sustainability is becoming a necessity. 3D food printing could probably contribute to the solution. Some experts believe printers could use hydrocolloids( 水解胶体)from plentiful renewables like algae(藻类) and grass to replace the familiar ingredients(烹饪原 料). 3D printing can reduce fuel use and emissions. Grocery stores of the future might stock "food" that lasts years on end, freeing up shelf space and reducing transportation and storage requirements.

    Nutrition

    Future 3D food printers could make processed food healthier. Hod Lipson, a professor at Columbia University, said, "Food printing could allow consumers to print food with customized nutritional content, like vitamins. So instead of eating a piece of yesterday's bread from the supermarket, you'd eat something baked just for you on demand."

    Challenges

    Despite recent advancements in 3D food printing，the industry has many challenges to overcome. Currently, most ingredients must be changed to a paste( 糊状物)before a printer can use them, and the printing process is quite time-consuming, because ingredients interact with each other in very complex ways. On top of that, most of the 3D food printers now are restricted to dry ingredients, because meat and milk products may easily go bad. Some experts are doubtful about food printers, believing they are better suited for fast food restaurants than homes and high-end restaurants.

    People who play computer games to train their brains might as well be playing Super Mario, new research suggests.

    In a six-week study, experts found people who played online games designed to improve their cognitive(认知的) skills didn't get any smarter.

    More than 8,600 people aged 18 to 60 were asked to play online brain games designed by the researchers to improve their memory, reasoning and other skills, for at least 10 minutes a day, three times a week.

    They were compared to more than 2,700 people who didn't play any brain games, but spent a similar amount of time surfing the Internet. All participants were given an "IQ test" before and after the experiment.

    Researchers said the people who did the brain training didn't do any better on the test after six weeks than people who had simply been on the Internet.

    "If you're(playing these games) because they're fun, that's absolutely fine," said Adrian Owen, assistant director at Britain's Medical Research Council. "But if you're expecting these games to improve your IQ, our data suggests this isn't the case."

    Computer games that are supposed to improve memory, reasoning and other cognitive skills are played by millions of people worldwide, though few studies have examined if the games work.

    "There is precious little evidence to suggest the skills used in these games transfer to the real world," said Art Kramer, a professor of psychology at the University of Illinois, US.

    Instead of playing brain games, Kramer said people would be better off getting some exercise. He said physical activity can help produce new brain cells.

    Other experts said brain games might be useful, but only if they weren't fun.

    "If you set the level for these games to a very high level where you don't get the answers very often and it really annoys you, then it may be useful," said Philip Adey, a professor of psychology at King's College in London.

    If people are enjoying the brain games, Adey said they probably aren't being challenged and might as well be playing a regular video game.

    He said people should consider learning a new language or sport if they really want to improve their brain power. "To stimulate(激发) the intellect, you need a real challenge," Adey said, "Getting smart is hard work."

    An 80-year-old man was sitting on the sofa in his house along with his 45-year-old highly educated son.

    Suddenly a crow (乌鸦) perched on the tree near their window.

    The father asked his son, "What is this?"

    The son replied, "It is a crow."

    After a few minutes, the father asked his son the second time, "What is this?"

    The son said, "Father, I have just now told you. It is a crow!"

    After a little while, the old father again asked his son the third time, "What is this?"

    "It's a crow, a crow, a crow!" said the son loudly.

    A little after, the father again asked his son the fourth time, "What is this?" This time the son shouted at his father, "Why do you keep asking me the same question again and again? 'IT IS A CROW'. Are you not able to understand this?"

    A little later the father went to his room and came back with an old diary, which he had kept since his son was born. On opening a page, he asked his son to read that page. When the son read it, the following words were written in the diary:

    "Today my little son aged three was sitting with me on the sofa, when a crow was sitting on the window. My son asked me 23 times what it was, and I replied to him all 23 times that it was crow. I hugged him lovingly each time he asked me the same question again and again for 23 times. I did not at all feel annoyed; I rather felt affection for my innocent child."

    Put an ice cube(小冰块) from your fridge into a glass of water. You have a piece of string(线) 10 centimeters long. The problem is to take out that piece of ice with the help of the string. But you must not touch the ice with your fingers (手指).

    You may ask your friends to try to do that when you are having dinner together. There is a saltcellar on the table. You must use salt when you carry out this experiment.

    First you put the string across the piece of ice. Then put some salt on the ice. Salt makes ice melt(融化). The ice round the string will begin to melt. But when it melts, it will lose heat. The cold ice cube will make the salt water freeze(冻结) again.

    After a minute or two you may raise(提起) the piece of string and with it you will raise your piece of ice!

    This experiment can be very useful to you. If, for example, there is ice near the door of your house, you must use very much salt to melt all the ice. If you don't put enough salt, the water will freeze again.