When a Swedish ship that sank（沉） in 1628 was recovered from the port of Stockholm, histor

When a Swedish ship that sank（沉） in 1628 was recovered from the port of Stockholm, historians and scientists were overjoyed with the chance to examine the remains of the past. The ship construction showed how ships were built and operated during the seventeenth century. In this way, artifacts, objects made by human beings, provided a picture of daily life almost 400 years ago.
Underwater archaeology(考古)-the study of ships, aircraft and human settlements that have sunk under large bodies of water-is really a product of the last 50 years. The rapid growth of this new area of study has occurred because of the invention of better diving equipment. Besides the Swedish ship wreck(残骸），underwater archaeologists have made more exciting discoveries such as the 5000-year-old boats in the Mediterranean Sea.
Underwater archaeology can provide facts abut the past. In ancient ports all over the world are ships sunken in the past 6, 000 years. There are also sunken settlements in seas and lakes telling of people’s way of life and their systems of trade in ancient times. Underwater archaeologists want to study these objects to add to the world's knowledge of history, but they have to fight two enemies. One enemy is treasure hunters who dive for ancient artifacts that they can sell to collectors. Once sold, these objects are lost to experts. The second enemy is dredging machines(挖掘机）often used to repair ports. These machines destroy wrecks and artifacts or bury them deeper under sand and mud. By teaching the public about the importance of underwater “museums” of the past, archaeologists are hoping to get support for laws to protect underwater treasures.
【小题1】What purpose does Paragraph 1 serve in the passage?A．To provide background information of the topicB．To attract readers' attention to the topicC．To use an example to support the topicD．To offer basic knowledge of the topic【小题2】The aim of underwater archaeology is to . A．exploit(开发)water bodies B．search for underwater lifeC．study underwater artifacts D．examine underwater environment【小题3】Underwater archaeologists are worried because . A．sea hunters have better diving equipment　B．their knowledge of world history is limited　C．dredging machines cause damage to the ports　D．sold artifacts can hardly be regained for research【小题4】What is the main purpose of the passage?A．To introduce a young branch(分支) of learning. B．To discuss the scientists’ problems. 　C．To explain people’s way of life in the past. 　D．To describe the sunken ships.B

(答案→)B 解析：文章主要告诉我们的是考古学重要的一个分支——水下考古以及水下考古的目的，面临的困境等。【小题1】B 推理题。文章用瑞典斯德哥尔摩港口的一艘沉船来引起读者的兴趣，来引起下文。故B正确。【小题2】C 细节题。根据第二段前两行Underwater archaeology(考古)-the study of ships, aircraft and human settlements that have sunk under large bodies of water-is really a product of the last 50 years.说明水下考古的目的是为了研究水下的文物，以此来研究历史。故C正确。【小题3】D 细节题。根据第三段倒数第五行Once sold, these objects are lost to experts.说明一旦这些文物被倒卖，专家们就无法去研究了，故D正确。【小题4】A 主旨大意题。文章主要告诉我们的是考古学重要的一个分支——水下考古，以及水下考古的目的，面临的困境等。故A正确。

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