【A】

        Palaces are known for their beauty and splendor, but they offer little protection against attacks. It is easy to defend a fortress, but fortresses are not designed with the comfort of a king or queen in mind. When it comes to structures that are both majestic and well-fortified, the classic European castle is the pinnacle of design. Across the ages castles changed, developed, and eventually fell out of use, but they still command the fascination of the English culture. 

       Castles were originally built in England by Norman invaders in 1066. As William the Conqueror advanced through England, he fortified key positions to secure the land he had taken. The castles he built allowed the Norman lords to retreat to safety when threatened by English rebellion. Castles also served as bases of operation for offensive attacks. Troops were summoned to, organized around, and deployed from castles. In this way castles served both offensive and defensive roles in military operations.

        Not limited to military purposes, castles also served as offices from which the lord would administer control over his fiefdom. The lord of the land would hold court in his castle. Those who were socially beneath the lord would come to report the affairs of the lands that they governed and pay tribute to the lord. They would address disputes, handle business, feast, and enjoy festivities. In this way castles served as important social centers in medieval England. Castles also served as symbols of power. Built on prominent sites overlooking the surrounding areas, castles constantly loomed in the background of many peasants’ lives and served as a daily reminder of the lord’s strength. 

       The first castles constructed in England were made from earth and timber. Those who constructed them took advantage of natural features, such as hills and rivers, to increase defenses. Since these castles were constructed from wood, they were highly susceptible to attacks by fire. Wooden castles were gradually replaced by stone, which greatly increased the strength of these fortifications； however, being made from stone did not make these castles entirely fireproof. Attackers could hurl flaming objects into the castle through the windows or ignite the wooden doors. This led to moving the windows and entrances off of the ground floor and up to the first floor to make them more difficult to access.

      As the nobility accumulated wealth, England became increasingly attractive to those who sought to plunder. Raids by Vikings and other marauders increased in regularity. In response to these attacks, castle defenses were updated and improved. Arrow-slits were added. These were small holes in the castle, large enough for an arrow to fit through, which allowed defenders to fire from nearly invulnerable positions. Towers were built from which defenders could provide flanking fire. These towers were connected to the castle by wooden bridges, so that if one tower fell, the rest of the castle was still easy to defend. Multiple rings of castle walls were constructed, so that even if attackers made it past one wall, they would be caught on a killing ground between inner and outer walls. Advances such as these greatly increased the defense of castles.

    The demise of castles can ultimately be attributed to gunpowder. Gunpowder was first introduced to Europe during the 14th century, but the first gunpowder weapons were unreliable, inaccurate, and weak by later standards. During the 15th century, artillery became powerful enough to break through stone walls. This greatly undermined the military role of castles. Castles were then replaced by artillery forts that had no role in civil administration and country houses that were indefensible. Though castles no longer serve their original purposes, remaining castles receive millions of visitors each year from those who wish to experience these majestic vestiges of a time long passed.

Choose the best answer for each missing word or phrase in the passages. 

Beer is nearly as old as recorded history. Man is believed to 24 beer at about the same time 25 learned to make bread. Archaeological evidence indicates that beer 26 produced in Mesopotamia around 6000 B. C. In the earliest 27 civilization, ancient Sumer in the near East, about forty percent of the grain crop went to make beer, and 28 was apparently also used for currency by the local nobility. Beer, bread, and onions probably formed the basic diet of the ancient Egyptian people, and some of their beer had an alcoholic content of up to twelve percent. The Greeks carried the art of brewing from Egypt into Europe, and the Romans learned about beer drinking during 29 conquest of Greece. Brewing rapidly took hold in northern and Western Europe where grape-growing was impractical because of the weather.

(1.) 

Our eyes and ears might be called transformers because they sense the light and sound around us and turn them into electrical impulses that the brain can interpret. These electrical impulses that have been transformed by the eyes and ears reach the brain and are turned into messages that we can interpret. For the eye, the process begins as the eye admits light waves, bends them at the cornea and lens, and then focuses them on the retina. At the back of each eye, nerve fibers bundle together to form optic nerves, which join and then split into two optic tracts. Some of the fibers cross so that part of the input from the right visual field goes into the left side of the brain, and vice versa. The process in the ear is carried out through sensory cells that are carried in fluid-filled canals and that are extremely sensitive to vibration. Sound that is transformed into electricity travels along nerve fibers in the auditory nerve. These fibers form a synapse with neurons that carry the messages to the auditory cortex on each side of the brain.