Nothing dries sooner than a tear.以下是小編為大家搜尋整理的2017年公共英語考試四級臨考衝刺練習題，希望能給大家帶來幫助!更多精彩內容請及時關注我們應屆畢業生考試網!
part 1
Vision
Human vision like that of other primates has evolved in an arboreal environment. In the dense complex world of a tropical forest, it is more important to see well than to develop an acute sense of smell. In the course of evolution members of the primate line have acquired large eyes while the snout has shrunk to give the eye an unimpeded view. Of mammals only humans and some primates enjoy color vision. The red flag is black to the bull. Horses live in a monochrome world. Light visible to human eyes however occupies only a very narrow band in the whole electromagnetic spectrum. Ultraviolet rays are invisible to humans though ants and honeybees are sensitive to them. Humans have no direct perception of infrared rays unlike the rattlesnake which has receptors tuned into wavelengths longer than 0.7 micron. The world would look eerily different if human eyes were sensitive to infrared radiation. Then instead of the darkness of night, we would be able to move easily in a strange shadowless world where objects glowed with varying degrees of intensity. But human eyes excel in other ways. They are in fact remarkably discerning in color gradation. The color sensitivity of normal human vision is rarely surpassed even by sophisticated technical devices.
視覺
人類的視覺，和其它靈長目動物的一樣，是在叢林環境中進化出來的。在稠密、複雜 的熱帶叢林裡，好的視覺比靈敏的嗅覺更加重要。在進化過程中，靈長目動物的眼睛變大，同時鼻子變小以使視野不受阻礙。在哺乳類動物中，只有人和一些靈長目動物能夠分辨顏色。紅旗在公牛看來是黑色的，馬則生活在一個單色的世界裡。然而，人眼可見的光在整個光譜中只佔一個非常狹窄的頻段。人是看不到紫外線的，儘管螞蟻和蜜蜂可以感覺到。與響尾蛇不同，人也不能直接感受到紅外線。響尾蛇的感覺器可以感受波長超過.7 微米的光線。如果人能感受到紅外線的話，這世界看上去將十分不同，而且恐怖。到那時，將與夜的黑暗相反，我們能輕易地在一個奇異的沒有陰影的世界裡走動。任何物體都強弱不等地閃著光。然而，人眼在其它方面有優越之處。事實上，人眼對顏色梯度具有非凡的分辨能力。普通人類的視覺感受色彩的靈敏程度，甚至連精密的技術裝備都很難超越。
part 2
Changing Roles of Public Education
One of the most important social developments that helped to make possible a shift in thinking about the role of public education was the effect of the baby boom of the 1950's and 1960's on the schools. In the 1920's, but especially in the Depression conditions of the 1930's, the United States experienced a declining birth rate —— every thousand women aged fifteen to forty-four gave birth to about 118 live children in 1920，89.2 in 1930，75.8 in 1936, and 80 in1940. With the growing prosperity brought on by the Second World War and the economic boom that followed it young people married and established households earlier and began to raise larger families than had their predecessors during the Depression. Birth rates rose to 102 per thousand in 1946, 106.2 in 1950, and 118 in 1955. Although economics was probably the most important determinant, it is not the only explanation for the baby boom. The increased value placed on the idea of the family also helps to explain this rise in birth rates. The baby boomers began streaming into the first grade by the mid 1940's and became a flood by 1950. The public school system suddenly found itself overtaxed. While the number of schoolchildren rose because of wartime and postwar conditions, these same conditions made the schools even less prepared to cope with the flood. The wartime economy meant that few new schools were built between 1940 and 1945. Moreover, during the war and in the boom times that followed, large numbers of teachers left their profession for better-paying jobs elsewhere in the economy.
Therefore in the 1950's and 1960's, the baby boom hit an antiquated and inadequate school system. Consequently, the "custodial rhetoric"of the 1930's and early 1940's no longer made sense that is, keeping youths aged sixteen and older out of the labor market by keeping them in school could no longer be a high priority for an institution unable to find space and staff to teach younger children aged five to sixteen. With the baby boom, the focus of educators and of laymen interested in education inevitably turned toward the lower grades and back to basic academic skills and discipline. The system no longer had much interest in offering nontraditional, new, and extra services to older youths.
公共教育的角色變化
一項重要的、有可能促使人們對公共教育的角色的看法發生轉變的社會發展是本世紀五六十年代的生育高峰對學校的影響。在 20 年代，尤其是在 30 年代後的大蕭條中，美國經歷了一次出生率的下降——1920 年每千名年齡在 15 歲至 45 歲的婦女生下大約 118 個存活嬰兒，1930 年 89.2 個，1936 年 75.8 個，1940 年 80 個。隨著二戰帶來的持續繁榮以及隨之而來的經濟增長，年輕人比大蕭條中的同齡人更早地結婚成家，而且比前輩養育更大的家庭。1946 年出生率上升到 102%，1950 年達 106%，1955 年達 118%。對於生育高峰，經濟有可能是最重要的決定因素，但它並不是唯一的解釋。不斷受到重視的家庭觀念也有助於解釋出生率的上升。到 40 年代中期為止，這些生育高峰出生的`孩子們開始源源不斷地進入國小一年級。到了 1950 年，就形成了一股洪流。公共教育系統突然感到不堪重負了。由於戰時和戰後的狀況，使得學齡兒童人數增加，這些狀況使得學校面對這股洪流更加措手不及。戰時經濟意味著在 1940 年到 1950 年間幾乎沒有建立新學校。而且，在戰時和隨後的經濟增長時期，大量的教師離開崗位去別處從事報酬更為優厚的工作。
因此，在五六十年代，生育高峰衝擊著陳舊而不完備的學校體系。這樣一來，30 年代以及 40 年代早期，"監護理論"就不再有意義了。也就是說，通過使 16 歲以上的年輕人留在學校不進入勞動力市場的做法再也不是教育機構的優先考慮了。因為教育機構不再能找到場地和教師來教育那些更 小的 5-16 歲的孩子。隨著生育高峰，教育者和圈外人士對教育的興趣和焦點，不可避免地轉向了更低的年級和基礎的學術技能和學科上。這個系統不再有濃厚的興趣給較年長的年輕人提供非傳統的新式的和額外的服務。
