Life is comprised emotion and sense. When we were babies we reached the pinnacle(顶峰) of emotion. At that time we asked for everything that we wanted, cried as we were uncomfortable, laughed as we were happy and released our emotions day and night. When we grow up we find that if we want to live in a cozier environment we must be sensible enough to deal with our emotions and relationships. Our world is based on sense and beautified by emotion.

    Sense is the base of life; it builds up the structure of life, and helps us see the real world. And emotion is the invaluable element of life. It adds colorful paint to our life. Lacking sense we may lose the guiding light and lacking emotion we may lose the value of life.

    We admire Da Vinci's Mona Lisa, we are attracted by Michelangelo's The Creation of Man, and we are carried away by Monet's Lotus. Shakespeare's Romeo and Juliet may bring us tears, Victor Hugo's poems can make a maid's love revive, and Jane Austin's stories arouse our dream of holding a party of ladies and gentlemen as an England beauty in the countryside. All of them are people who deserve our respect and showed us sentimental emotion: love, hatred, betrayal, loyalty and so on. They made their works full of emotion, shocked our nerves, and evoked our passions. Somebody may have found their destiny in these works, and surely they influence people time after time. But in fact, though these people or their works have the power to control our mental world, we don't choose them to be our President or Prime Minister. We cannot deny the fact that our world is based on sense and ration. Mark Twain once said that the passion of friendship is so sweet, steady and royal and enduring a nature that it will last through a whole lifetime if neither of the two friends asks the other to lend money.

    Emotion is our nature and sense gives us an eye to live in reality. Only sense makes Jack a dull boy; emotional moments give us vigor and enthusiasm to live and color our life.

    Every people uses its own special word to show its ideas and feelings. Some of these expressions（表达，说法） are commonly used for many years. Others are popular for just a short time. One such American expression is “Where's the beef?” It is used when something is not as good as it is said to be. In the early 1980s “Where's the beef?” was one of the most popular expressions in the United States. It seemed as if everyone using it at the time.

    Beef, of course, is the meat from a cow, and food is more popular in America than a hamburger made from beef. In the 1960s a businessman named Ray began building small restaurants that sold hamburgers at a low price. Ray called this “McDonald's”. Ray became one of the richest businessmen at last in America.

    Other business people watched his success. Some of them opened their own hamburger restaurants. One company called “Wendy's” said its hamburgers were bigger than those sold by McDonald's or anyone else. The Wendy's Company began to use the expression “Where's the beef?” to make people know that Wendy's hamburgers were the biggest. The Wendy's television advertisement showed three old women eating hamburgers. The bread that covered the meat was very big, but inside there was only a bit of meat. One of the women said she would not eat a hamburger with such a little piece of beef. “Where's the beef?” she shouted in a funny way. The advertisement for Wendy's hamburger restaurants was success. As we said, it seemed everyone began using the expression “Where's the beef?”.

    A layover (临时滞留) or flight delay can be extremely fun in these international airports.

Munich Airport, Germany

    Aviation (航空) lovers passing through Munich can take a behind－the－scenes tour to learn how the airport operates. Visitors can also tour three historic aircraft and a retired rescue helicopter, climb up to a 28－metre high observation platform for an up－close view of take－offs and landings, and watch films on aviation in the airport's 60－seat cinema. Travelers can also kill layover time at an 18－hole mini－golf course, or even stop in for a teeth cleaning at the airport dental office.

Changi Airport, Singapore

    After a long flight to Singapore, travelers can relax in a Balinese－style swimming pool, work out at the airport gym, or enjoy a drink and live musical performances at the airport's Music Bar. The airport also boasts a tranquil butterfly garden, and a “fragrant garden” which is home to 15 species of plants and trees. Free movies at one of two airport cinemas also keep passengers entertained.

    Schiphol Amsterdam Airport, the Netherlands

    Schiphol is Europe's fifth－largest airport. Here passengers can view the works of Dutch masters free of charge, and try their luck at airport's casino (赌场). You can even have your wedding ceremony at Schiphol—couples can choose from four different wedding packages, including a 1930－style ceremony held on a Dakota military aircraft.

    San Francisco International Airport, California

    The airport's 24－hour AirTrain not only moves passengers between terminal, but also provides a fun view of the runways. There are three aquariums (水族馆) to explore, along with interactive play areas, an aviation museum, and a library. If that's not enough to keep the little ones busy, travelers can rent portable DVD players and movies for use in the airport.

    It's a warm summer afternoon. You're cooking up the catch of the day over a campfire. Suddenly, a few raindrops fall on your arms, and before you know it, the sky is opened up. Then you hear what sounds like thunder in the distance. What should you do? Your tent is close by and would offer shelter from the pouring rain. There's a campsite picnic shelter a few minutes down the path. And then you remember that your car is parked down the road. What's your safest choice to make sure you and your families are safe?

    It's a common question for many hikers(徒步者) and campers, especially when they are camping during summer months. Heading to your car is almost always the safest choice. Your tent and a picnic shelter will keep you dry, but they offer little or no protection against lightening. Your car, on the other hand, will keep you dry and protect you from lightening strikes. Protecting yourself against possible lightening strikes is very important; lightening kills an average of 62 people in the US each year. If you keep all of the windows and doors closed in your car, you'll be able to return to your campsite safely.

    Of course, if you're backpacking(背包旅行), not car camping, and you're deep in the woods, your car won't be a good choice. So, what should you do if your car is far away and there's no other safe shelter nearby? First, you'll have to make sure that tree limbs or other objects don't fall on you or your campsite. Then you'll have to get in a safe position to avoid lightening, or flash flood conditions. What else should you do?

    A while back I caught a news report on something called -couch surfing‖ and the network of trusting souls who make this phenomenon possible. They offer to put up travelers free of charge and help them on their ways. At first, it sounded unbelievable. I mean, inviting strangers into one's home for one or two nights? Give me a break.

    However, I was intrigued. I decided to investigate. The only way to truly learn about this phenomenon was to dive in. So I planned a trip to Finland, a country I've always wanted to explore. I would couch surf at every stop there.

    If ever any anxiety existed when stepping into the unknown, it disappeared when my first host met me at the train station. Ari looked like my idea of a typical Finn: tall and blue-eyed. Finns were also supposed to be famously reserved (寡言少语的). Ari was anything but. He was a live wire, giving me an enthusiastic welcome and hiking with me to his apartment, where he showed me the sleeper sofa, served me tea, and engaged me in warm conversations. He also handed me a key to come and go as I pleased.

    If this was what couch surfing was all about－trust and friendship－then I had gotten off to a good start. As I boarded my next train to continue my journey, I began to think about this couch-surfing idea. What urged these people to open their homes to strangers? I concluded that there was a desire to lend a hand to like-minded folks who might enrich their own lives.

    Seven cities in 14 days. Seven hosts. Seven new friends. If couch surfing taught me anything, it's this: Most people are good and generous. Where will couch surfing take me next? Who knows? But I can't wait to find out.

Crocodiles today look very similar to ones from 200 million years ago. There are also very few species alive today—just 25. Other animals such as lizards (蜥蜴) and birds have achieved a diversity of many thousands of species in the same amount of time or less.

Prehistory also saw types of crocodile we don't see today, including giants as big as dinosaurs, plant-eaters, fast runners and snake-like forms that lived in the sea. The rate of their evolution is generally slow, but occasionally they evolve more quickly because the environment has changed. In particular, their evolution speeds up when the climate is warmer, and their body size increases.

The body size of crocodiles is important because it interacts with how fast animals grow, how much food they need, how big their populations are and how likely they are to become extinct. The limited diversity of crocodiles and their apparent lack of evolution is a result of a slow evolutionary rate. It seems the crocodiles arrived at a body plan that was very efficient and perfect enough that they didn't need to change it in order to survive. This perfection could be one explanation why crocodiles survived Cretaceous period (白垩纪), in which the dinosaurs died out.

Crocodiles generally develop better in warm conditions because they cannot control their body temperature and require warmth from the environment. The climate during the age of dinosaurs was warmer than it is today, and that may explain why there were many more varieties of crocodiles than we see now. Being able to draw energy from the sun means they do not need to eat as much as a warm-blooded animal like a bird or a mammal (哺乳动物).