When the Normans built their first simple wooden castles in England，they built them on the top of small hills.The first permanent castles were made of stone and built with thick walls.The main building was usually surrounded by walls which overlooked the moat (护城河)．

     The entrance to the castle was usually over a drawbridge (吊桥) leading to the main gatehouse.The drawbridge could be raised or lowered and an iron grille (栅栏) could be lowered to shut off the entrance to the gatehouse.

     As time went on，the castle builders became more advanced in their techniques.Instead of building a strong central building and surrounding it with walls of lesser strength，they thought out the idea of surrounding a central area with huge walls which could contain all the main rooms of the castle.These walls usually had many towers and these towers were really a series of main buildings along the castle walls.In building these castles they used hill sites whenever possible in order to give the castle a better position.Because the outside world was shut off by a barrier or curtain of defences，they are called “curtain wall” castles.

     With the passing of time there was less need to build strong castles and nobles built manor (庄园) houses.These manor houses often had battlements and iron grilles，but they were built more for comfort and included many of the conveniences and luxuries of the large houses which were being built in the towns.

     Unfortunately，many English castles were damaged or destroyed completely during the Civil Wars of the 1600s.

    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.

    My senior years, I can't believe it is almost over. Now when I look back, it was stressful, but exciting, the ball, graduation, and then of course, college.

    I started applying for my college months before Christmas. My parents told me it would be smart if I set up interviews and tours. But I wasn't motivated. I wanted to go to college, but I didn't want to deal with the stress.

    As the days flew by, my applications lay on my desk just as I had left them three months before. “You are wasting valuable time,” my parents complained. Sweeping away the gathered dust on the applications, I worked on them every Sunday until I finished. Next came writing the essays. I had many ideas, but every school had different requirements. I changed them until I was pleased. Finally, everything was underway.

    Now I just had to wait. In March, I started receiving letters of rejection. I began to think that I had set myself up for disappointment. I had a letter from Salem State College starting that they wanted to see my grades before they made their decision. Yes! At least someone wanted to consider me. At the beginning of April, I received a letter from Keens State. Those opening words: “We regret to inform you…” made me sit down and cry. I had lost all hope. Then I heard from Plymouth State. Not my first choice, but…I had been accepted. Maybe if I get my grades up, I can choose another school…

    The college application hurt me deeply. All my friends had dozens of schools to choose from. I guess my parents were right. High school grades are undoubtedly important to your future plans. If I could do it all over again, I would take it more seriously.

    We often hear stories of animals rescuing people. But now someone has managed to return the favor.

    The event took place one snowy January morning Thomas Smith was walking his dog, Jack, in the park." As I was walking, I just saw Jack running onto the ice towards the ducks in the middle, and then he fell into the water and couldn't climb out, "said Smith. He realized he had no choice but to try and save his dog. "Someone else told me the lake was only one-meter deep, but it was at least twice that. I had to break my way through the 6-cm ice. Finally, I got Jack by the neck, and pulled him out. I don't think I have ever felt so cold by the time we got back to dry land. And when we got there, everyone was asking if Jack was okay no one was particularly worried, about me!"

    A neighbor, Julie Brown, saw it all happen. "The dog went onto an icy lake. All of a sudden, it started to go under. There were crowds of people around, and they were all shouting and screaming. Before I knew it, the owner Smith was in the water forcing his way through the ice. I can't begin to imagine how cold it was. Everyone was very nervous, but he was as cool as a cucumber he just crawled back out, put the dog on its lead, and went home."

    Many regard him as a hero, but Mr. Smith is quite laid-back about it. "Most dog owners are the same as me. They would do what I did without a second thought. But in the future, I'm going to make sure he's on lead near any ice ponds, Pets are members of our family. Would you do the same for them?

Every profession or trade, every art, and every science has its technical vocabulary, the function of which is partly to name things, or processes which have no names in ordinary English, and partly to secure greater exactness in terminology (术语). Such special dialects are necessary in technical discussion of any kind. Being universally understood by those engaged or interested in the particular science or art, they have the accurateness of a mathematical formula (公式）. Besides，they save time in these kinds of discussions, for it is much more economical to name a process than to describe it. Thousands of these technical terms are very properly included in every large dictionary, yet, as a whole, they are rather in the suburbs of the English language.

Different occupations, however, differ widely in the character of their special vocabularies. In trades and handicrafts, and other professions, like farming and fishery, which have occupied great numbers of men from remote times, the technical vocabulary is very old. It consists largely of native words, or of borrowed words that have worked themselves into the very central part of our language. Thus, though highly technical in many particulars, these vocabularies are more familiar in sound, and more generally understood, than most other technical terms. In law, medicine, and philosophy, the special dialects have also become pretty familiar to cultivated persons and have contributed much to the popular vocabulary. Yet among these professions, each one still possesses a large body of technical terms that remain essentially foreign, even to educated speech. And the proportion has increased in the last fifty years, particularly in the various departments of natural and political science and in the mechanic arts. Here new terms are coined with the greatest freedom, and abandoned when they have served their turn. Most of the newly-invented terms are restricted to special discussions, and seldom get into general literature or conversation.

Yet no profession is nowadays, as all professions once were, a close combination. Lawyers, doctors and men of science all communicate freely with others, not in a merely professional way. Furthermore, what is called "popular science" makes everybody familiar with modem views and recent discoveries. Any important experiment, though made in a remote or provincial laboratory, is at once reported online, and everybody is soon talking about it-as in the case of AI.

Four Books about Curious Creatures

In these brilliant books find out about fleas, foxes and some unexpected friendships. 

Animal Sidekicks

by Macken Murphy.

Illustrated by DraganKordic

This illustrated book explores the idea of symbiosis—animals that form amazing relationships to help each other. Youˈll learn about clownfish living peacefully with poisonous sea anemone, the frog that lives with a tarantula, and lots more. 

The Secret Life of Foxes

by ChloePetrylak.

Have you ever spotted a fox on the streets of your town at night or even in your back garden? Wildlife enthusiasts will love finding out more about the mysterious lives of foxes. As well as lots of interesting information, this book includes great ideas for ways to help foxes near you. 

PleaseDonˈt Bite Me

by Nazzy Pakpour.

Illustrated by Owen Davey

Did you know that wasps can build nests as much as five metres wide? Or that fleas can jump 150 times their own height? How do mosquitoes track you down? This interesting illustrated book digs out the surprising lives of some of the buzzing, biting and stinging insects that are all around. 

Stone Age Beasts

by BenLerwill.

Illustrated by Grahame Baker-Smith

Travel back in time to meet incredible creatures in this beautiful book. It features many of the prehistoric animals that our human ancestors would have met face-to-face in the Stone Age. Learn about the woolly mammoth, the sabre-toothed cat, and the six-metre snake that once slithered along the forest floor.