43
(A) a way of life
(B) a way out
(C) the right way up
(D) a long way off

49.Crime rate in post-war America has ________. (A) become less organized (B)declined (C) climbed (D)remained about the same

50.Despite all the negative aspects he saw in post-war America,the article thinks America is______(A)the best hope for rich and fame (B) the best hope for freedom(C)the worst hope for freedom (D)the last hope for survival

41 (A) introduced (B) intruded (C) invited (D) invaded

42 (A) imperiously (B) instinctively (C) instantaneously (D) interchangeably

44 (A) Therefore (B) Unfortunately (C) Frankly (D) Nevertheless

45 (A) altered (B) mystified (C) diluted (D) offered

46 What is the main idea of the passage? (A) After two decades of lab research, gene therapy in humans has been successful in treating everything from cancer to Alzheimer’s to heart disease. (B) A lot of research in gene therapy has focused on getting a gene to its destination and coaxing it to turn on once inside a cell. (C) Although research has been done on how gene therapy can help treat serious diseases, such a treatment may cause irreversible side effects and unknown consequences. (D) Viral vectors like Trojan horses slip genes into target cells undetected.

47 “Viral vectors” are _____ . (A) ways with which viruses genomes are changed (B) viruses used for carrying genetic material into cells (C) the paths through which viruses move (D) immune reactions triggered by viral infection

48 What does the word “trigger” mean in the passage? (A) Activate (B) Shoot (C) Turn off (D) Plug

49 According to the passage, which of the following statements is NOT correct? (A) Genes are unable to move across cell membranes on their own. (B) Gene therapy is still in its early stages. (C) Scientists have made significant progress in taking control of viruses that carry therapeutic genes. (D) Much effort in gene therapy has been spent to deceive cells into accepting foreign genes.