Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50.
 The need for a surgical operation, especially an emergency operation, almost always comes as a severe shock to the patient and his family. Despite modern advances, most people still have an irrational fear of hospitals and anaesthetics. Patients do not often believe they really need surgery- cutting into a part of the body as opposed to treatment with drugs.
In the early year of the 20th century, there was little specialization in surgery. A good surgeon was capable of performing almost every operation that had been advised up to that time. Today the situation is different. Operations are now being carried out that were not even dreamed of fifty years ago. The heart can be safely opened and its valves repaired. Clogged blood vessels can be clean out, and broken ones mended and replaced. A lung, the whole stomach, or even part of the brain can be removed and still permit the patient to live a comfortable and satisfactory life. However, not every surgeon wants to, or is qualified to carry out every type of modern operation.
The scope of surgery has increase remarkably in the past decades. Its safety has increased, too. Deaths from most operations are about 20% of what they were in 1910 and surgery has been extended in many directions, for example, to certain types of birth defects in new born babies, and at the other end of the scale, to life-saving operation for the octogenarian. The hospital stay after surgery has been shortened to as little as a week for most major operations. Most patients are out of bed on the day after an operation and may be back at work in two or three weeks.
One of the most revolutionary areas of modern surgery is that of organ transplants. Until a few decades ago, no person, except an identical twins, was able to accept into his body the tissues of another person without reacting against them and eventually killing them. Recently, however, it has been discovered that with the use of X-rays and special drugs, it is possible to graft tissues from one person to another which will survive for periods of a year or more. Kidneys have been successfully transplanted between non-identical twins. Heart and lung transplants have also been reasonably successful.
“Spare parts” surgery, the simple routine replacement of all worn-out organs by new ones, is still a dream of the future but surgery is ready for such miracles. In the meantime, you can be happy if the doctors say to you: “Yes, I think it is possible to operate on you for this condition.”
The main difficulty with organ transplants is  _____.
A.it is difficult to find organs of the same size
B.only identical twins can give permission for their organs to be exchanged
C.the body’s tendency to reject alien tissues
D.the patient is not allowed to use drugs after them

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Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following questions.
              Plants are subject to attack and infection by a remarkable variety of symbiotic species and have evolved a diverse array of mechanisms designed to frustrate the  potential colonists. These can be divided into preformed or passive defense mechanisms  and inducible or active systems. Passive plant defense comprises physical and chemical  barriers that prevent entry of pathogens, such as bacteria, or render tissues unpalatable or toxic to the invader. The external surfaces of plants, in addition to being covered by an epidermis and a waxy cuticle, often carry spiky hairs known as trichomes, which either prevent feeding by insects or may even puncture and kill insect larvae. Other trichomes are sticky and glandular and effectively trap and immobilize insects. If the physical barriers of the plant are breached, then preformed chemicals may inhibit or kill the intruder, and plant tissues contain a diverse array of toxic or potentially toxic substances, such as resins, tannins, glycosides, and alkaloids, many of which are highly effective deterrents to insects that feed on plants. The success of the Colorado beetle in infesting potatoes, for example, seems to be correlated with its high tolerance to alkaloids that normally repel potential pests. Other possible chemical  defenses, while not directly toxic to the parasite, may inhibit some essential step in the establishment of a parasitic relationship. For example, glycoproteins in plant cell walls may inactivate enzymes that degrade cell walls. These enzymes are often produced by bacteria and fungi.
            Active plant defense mechanisms are comparable to the immune system of  vertebrate animals, although the cellular and molecular bases are fundamentally different. Both, however, are triggered in reaction to intrusion, implying that the host has some means of recognizing the presence of a foreign organism. The most dramatic example of an inducible plant defense reaction is the hypersensitive response. In the hypersensitive response, cells undergo rapid necrosis ― that is, they become diseased and die ― after being penetrated by a parasite ; the parasite itself subsequently ceases to grow and is therefore restricted to one or a few cells around the entry site. Several theories have been put forward to explain the bases of hypersensitive resistance.
Where in the passage dose the author describe an active plant-defense reaction?
A.Lines 1-3
B.Lines 13-15
C. Lines 19-23
D.Lines 4-6

Read the passage carefully and choose the correct answer.
Jean spent her first few years in Hooper and her family moved to Otsego early in her life. She was only ten when her father died unexpectedly, leaving her mother to raise and support their family alone. Her mother soon went to work outside the home to provide for the family, and Jean, being one of the oldest, had to help care for her younger siblings. Although she had much responsibility at home, Jean thoroughly enjoyed school and was an excellent student. She went on to graduate 10th in her class at Otsego High School in 1953.
While still in high school, Jean met a young man named Charles "Chuck" Holly, at a dance in Alamo; and they were quite taken with each other. Over the next few years, their love for each other blossomed and they were married on February 24, 1953, while Jean was still in school. At the time, Chuck was serving his country in the military, and had come home on leave to marry his sweetheart. Unfortunately, shortly thereafter, he was sent overseas to serve in Korea for the next fifteen months.
Upon his discharge, the couple settled into married life together in the Plainwell, Otsego area. To help make ends meet, Jean went to work at the collection bureau in Kalamazoo for a while, before taking a job at the cheese company in Otsego. In 1964, Chuck and Jean were overjoyed with the birth of their son, Chuck, who brought great joy into their lives. Jean remembered how her mother was always gone so much working after her father died and she did not want that for her son, so she left her job to devote herself to the role of a mother.
Jean's husband was a _______.
A.teacher  
B.dancer    
C.soldier       
D.servant