One day, Mr. Arnold was teaching a lesson, and things were going as normally as ever. He was explaining the story of human being to his pupils. He told them that, in the beginning, men were nomads (游牧); they never stayed in the same place for very long. Instead, they would travel about, here and there, in search of food, wherever it was to be found. And when the food ran out, they would move off somewhere else.

    He taught them about the invention of farming and keeping animals. This was an important discovery, because by learning to cultivate (耕作) the land, and care for animals, mankind would always have food steadily. It also meant that people could remain living in one place, and this made it easier to set about tasks that would take a long while to finish, like building towns, cities, and all that were in them. All the children were listening attracted by this story, until Lucy jumped up:

    “And if that was so important and improved everything so much, why are we nomads all over again, Mr. Arnold?”

    Mr. Arnold didn't know what to say. Lucy was a very clever girl. He knew that she lived with her parents in a house, so she must know that her family were not nomads; so what did she mean?

    “We have all become nomads again,” continued Lucy, “The other day, outside the city, they were cutting the forest down. A while ago a fisherman told me how they fish. It's the same with everyone: when there's no more forest left the foresters go elsewhere, and when the fish run out the fishermen move on. That's what the nomads did, isn't it?

    The teacher nodded, thoughtfully. Really, Lucy was right. Mankind had turned into nomads. Instead of looking after the land in a way that we could be sure it would keep supplying our needs, we kept developing it until the land was bare. And then off we would go to the next place! The class spent the rest of the afternoon talking about what they could do to show how to be more civilized (文明的).

    The next day everyone attended class wearing a green T-shirt, with a message that said “I am not a nomad!”

    And, from then on, they set about showing that indeed they were not. Every time they knew they needed something, they made sure that they would get it using care and control. If they needed wood or paper, they would make sure that they got the recycled kind. They ordered their fish from fish farms, making sure that the fish they received were not too young and too small. They only used animals that were well cared for, and brought up on farms.

    And so, from their little town, those children managed to give up being nomads again, just as prehistoric men had done, so many thousands of years ago.

    It is a tall tale（夸张的故事）that terrifies most young children. Swallow a piece of chewing gum and it will remain in your body for seven years before it is digested. An even worse tale is that swallowed（吞） gum can wrap itself around your heart.

    But what does happen if you should accidentally eat a stick of gum? Chewing gum is made out of gum base, sweeteners, coloring and flavoring. The gum base is pretty indigestible(难消化的)—it is a mixture of different ingredients (成分) that our body can't absorb.

    Most of the time, your stomach really cannot break down the gum the way it would break down other foods. However, your digestive system has another way to deal with things you swallow. After all, we eat lots of things that we are unable to fully digest. They keep moving along until they make it all the way through the gut (肠子) and come out at the other end one or two days later.

    The saliva (唾液) in our mouths will make an attempt at digesting chewing gum as soon as we put it in our mouths. It might get through the shell（壳） but many of gum's base ingredients are indigestible. It's then down to our stomach muscles—which contract(收缩) and relax, much like the way an earthworm moves—to slowly force the things that we swallow through our systems.

    Swallowing a huge piece of gum or swallowing many small pieces of gum in a short time can cause a blockage within the digestive system, most often in children, who have a thinner digestive tube than adults—but this is extremely rare.

    I have an interest in photography and follow many photography Instagram accounts. Just like me, a friend of mine has a similar interest. The only difference is that he is a traveller and has taken hundreds of beautiful photos. He is really talented.

    Having returned from one trip, he shared some of his latest photos. Blown away by the images, I asked him why he hadn't started his own Instagram account of shots.

    “It's hard to start when there are already so many other websites devoted to travel photography with thousands of followers”, he explained. “What if I don't get any followers or what if people don't like my shots?”

    “Yet how will you ever know if you don't try?” I asked.

    He just shrugged and quickly changed the subject. I knew this feeling well. The feeling of self-doubt.

    That was when I was ten years old. I participated in a guitar competition. My grandfather helped me write a short speech to address the crowd and judges. But as the competition began, doubt consumed me and questions flooded my head. I thought to myself, “If I do say the speech, will the other girls laugh at me? Will the judges think I'm being silly for doing my own talk?”

    Then with a shake in my voice I said, “My name is Heidi Ceci. I live in St. Catharines and I play the guitar.” Nothing more... and nothing less.

    But the next girl walked up to the microphone and actually said a speech. I just stared at her in complete disbelief. No one seemed to be judging her for doing something different. In fact, they applauded louder for her than any other girl.

    From then on, I never let fear and doubt rule my decisions. Whatever happens, I always take chances and have a try.

                                                                                       Official Historical Tour of Harvard

    Student-Led Public Walking Tour

    Please note: Due to ongoing construction, our tour schedule will be limited. Please check our updated tour times on the calendar. In the event of bad weather, please check the calendar or call regarding a scheduled tour time.

    The tour is student-led and includes an outdoor walk(please dress appropriately)through Harvard Yard, providing a history of the university, general information, and a unique view on the students' individual experience. The tour is around one hour long, and completely free of charge. There is no pre—registration for general visitors, and we begin registration for each tour one hour before departure time. Currently we are only able to accommodate groups of up-to 14 people on our free, public tour. If you have a group of 15 or more, reservations are required (please see below).

    Group Tours and Reservations

    Reservations are required for tours of 15 or more people, with an absolute maximum of 125 people. We request 2 weeks' notice to schedule a tour. Please note that we cannot accommodate groups that arrive without a reservation.

    A Self-Guided Walking Tour of Harvard Yard

    If you are interested in touring the campus on your own,you may want a self-guided walking tour. These tour pamphlets(册),offered in nine different languages, can be purchased from our office for a minimal charge.

    You may also download audio files of historical information on each of the buildings in Harvard Yard. These files, together including an Audio Tour, can also be obtained here with a simple click.

    To personal trainer Sammy Callari, 13-year-old Parker Seward is more than a client(客户). He's his "little brother". Over the past year, the pair have bonded. They play basketball together, share meals and dance to hip-hop like no one's watching.

    The trainer was asked to work with the 13-year-old boy, who has Down syndrome(唐氏症), because his coworker who dealt with the boy was out of town last spring. Callari had never worked with someone with a disability before. He was anxious the first day he met Parker. But Parker's big smile and cheery introduction immediately put him at ease. He reminded Callari of himself when he was a teenager. Like Parker, Callari has also faced his fair share of challenges over the years.

    As a high schooler, Callari described himself as being the weak kid. When it came to sports, he was always overlooked. His dream of playing baseball in college quickly faded away. When he went to college, Callari turned to a new sport. His younger brother trained him to become a boxer. Callari participated in five matches. Out of four of those fights he was the underdog, and he won three times. "I know how it feels," Callari said. "Society tells you that you can't do this, you can't do that." When it comes to Parker, Callari refuses to accept the word "can't".

    The friends meet twice a week to train. They bike, box, run and work on their core with push-ups. Parker has a short attention span, so it's Callari's job to keep him focused. "If Parker can do it, if he's having fun, even with his frustration, then people will ask, "Why can't I do that?" Callari said. "That's the whole task right now."

    Callari recalls Parker's mom once thanking him for taking a "chance" on her son. Callari told her he never viewed it that way. Parker may be the student, but Callari says he's also the one who's learning.

    New England is the six northeastern states of the United States: Maine, New Hampshire, Vermont, Massachusetts, Rhode Island, and Connecticut. The six states were among the first colonies (殖民地) in America. The colonies were ruled by England, and this is how the area became known as New England. After the Revolutionary (革命的) War the colonies became states.

    Many things are similar in the six New England states. For example, there are many stone walls, fishing villages and forests in these states. The houses and buildings are similar, too. People cut down trees from the forests to make space for their farms and villages.

    They then used wood from the trees and stones from the field to build houses, schools, and churches. Even today, most of the houses in New England are made of wood.

    There are big cities in New England, but there are also small cities and farms, especially in the northern part. There is much industry and business and New England is one of the most populous (人口稠密的) parts of the United States. It has many busy seaports on its long coast. There are always many tourists who enjoy the beautiful lakes, beaches, and mountains and who visit the historical places.