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请完成下列Java程序；实现JComboBox，包含3个选项，分别是java、c++、vb，以及1个文本区，用于显示选择结果。 注意：请勿改动main()主方法和其他已有语句内容，仅在下划线处填入适当的语句。 源程序文件代码清单如下： import java.awt.event.*; import javax.swing.*; import java.awt.*; public class ex14_2 extends JFrame implements ItemListener { BorderLayout bLay = new BorderLayout(); JTextField jtf = new JTextField(27); JComboBox jcb = new JComboBox(); public ex14_2() { super ("ex14_2");//调用当前类ex14_2的父类JFrame的构造方法。 jcb.addItemListener(this); jcb.addItem("java"); jcb.addItem("c++"); jcb.addItem("vb"); jcb.setEditable(false); jtf.setHorizontalAlignment(SwingConstants.CENTER); jtf.setEditable(false); JPanel jp = new JPanel(); jp.setLayout(bLay); jp.add(jtf, "South"); jp.add(jcb, "Center"); setContentPane(jp); } public static void main(String[] args) { JFrame frame = new ex14_2(); frame.pack(); frame.setVisible(true); } public void itemStateChahged(ItemEvent ie) { Object o = if (o == job) { Object newO; ______; jtf.setText(newO.toString()+"被选中!"); } repaint(); } }
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A: Spot DictationDirections: In this part of the test, you will hear a passage and read the same passage with blanks in it. Fill in each of the blanks with the word or words you have heard on the tape. Write your answer in the corresponding space in your ANSWER BOOKLET. Remember you will hear the passage ONLY ONCE. What is distance learning It means that you study on your own, at home or wherever suits you. Recently, the world famous Open University in the United Kingdom has designed a new style of distance learning, which is called" (1) ". The phrase "Open Learning" means you study (2) . You read course material, work on course activities, and write (3) .The word "Supported" means you have help (4) , the student services staff at regional centres, and centralised areas such as (5) . You can also contact other students through tutorials and (6) , the University’s online conferencing system and events and dubs organised by (7) . Most distance learning courses use printed paper materials. They also include some (8) materials such as a CD, DVD or video. Many courses have a website and an (9) . You’ll need access to a computer (10) to make use of these. The Open University can help its students buy a computer and (11) the cost of accessing the Internet. With most distance learning courses, no (12) are required to study. Of course, you have to be aged 18 when your course starts but there is no (13) .Currently the Open University has around (14) undergraduate and more than 30,000 postgraduate students, of which 10,000 have (15) . Nearly all students are studying (16) . About 70 percent of undergraduate students are in (17) . More than 50,000 students (18) by their employers for their studies. Most distance learning courses (19) . Some of them are even available in other parts of the world. With over 25,000 of its students living outside the UK, the Open University is the (20) that offers distance learning throughout the world.
Americans do not go in for envy. The gap between rich and poor is bigger than in any other advanced country, but most people are unconcerned. Whereas Europeans fret about the way the economic pie is divided, Americans want to join the rich, not soak them. Eight out often, more than anywhere else, believe that though you may start poor, if you work hard, you can make pots of money. It is a central part of the American Dream. The political consensus, therefore, has sought to pursue economic growth rather than the redistribution of income, in keeping with John Kennedy’s adage that "a rising tide lifts all boats." The tide has been rising fast recently. Thanks to a jump in productivity growth after 1995, America’s economy has outpaced other rich countries’ for a decade. Its workers now produce over 30% more each hour they work than ten years ago. In the late 1990s everybody shared in this boom. Though incomes were rising fastest at the top, all workers’ wages far outpaced inflation.
中国坚定不移地走和平发展道路，是基于中国国情的必然选择。1840年鸦片战争以后的 100多年里，中国受尽了列强的欺辱。消除战争，实现和平，建设独立富强、民生幸福的国家，是近代以来中国人民孜孜以求的奋斗目标。今天的中国虽然取得了巨大的发展成就，但人口多，底子薄，发展不平衡，仍然是世界上最大的发展中国家。推动经济社会发展，不断改善人民生活始终是中国的中心任务。中国人民最需要、最珍爱和平的国际环境，愿尽自己所能，为推动各国共同发展作出积极贡献。
I have just come home after viewing some astonishing works of art that were recently discovered in Church Hole cave in Nottinghamshire. They are not drawings, as one would expect, but etchings, and they depict a huge range of wild animals. The artists who created them lived around 13,000 years ago, and the images are remarkable on a variety of counts. First of all, their sheer number is staggering, there are ninety all told. Moreover, fifty-eight of them are on the ceiling. This is extremely rare in cave art, according to a leading expert, Dr Wilbur Samson of Central Midlands University. Wall pictures are the norm, he says, "But more importantly, the Church Hole etchings are an incredible artistic achievement. They can hold their own in comparison with the best found in continental Europe." I am not a student of the subject, so I have to take his word for it. However, you do not have to be an expert to appreciate their beauty. In fact, it is the wider significance of the etchings that is likely to attract most attention in academic circles, since they radically alter our view of life in Britain during this epoch. It had previously been thought that ice-age hunters in this country were isolated from people in more central areas of Europe, but the Church Hole images prove that ancient Britons were part of a culture that had spread right across the continent. And they were at least as sophisticated culturally as their counterparts on the mainland. An initial survey of the site last year failed to reveal the presence of the etchings. The reason lies in the expectations of the researchers. They had been looking for the usual type of cave drawing or painting, which shows up best under direct light. Consequently, they used powerful torches, shining them straight onto the rock face. However, the Church Hole images are modifications of the rock itself, and show up best when seen from a certain angle in the natural light of early morning. Having been fortunate to see them at this hour, I can only say that I was deeply—and unexpectedly—moved. While most cave art often seems to have been created in a shadowy past very remote from us, these somehow convey the impression that they were made yesterday. Dr Samson feels that the lighting factor provides important information about the likely function of these works of art. "I think the artists knew very well that the etchings would hardly be visible except early in the morning. We can therefore deduce that the chamber was used for rituals involving animal worship, and that they were conducted just after dawn as a preliminary to the day’s hunting." To which I can only add that I felt deeply privileged to have been able to view Church Hole. It is a site of tremendous importance culturally and is part of the heritage, not only of this country, but the world as a whole. It is obvious that the writer______.
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