编辑：share 来源： 美联出国考试 发布时间：2016-10-17
Paragraph 3: The fossil consists of a complete skull of an archaeocyte, an extinct group of ancestors of modern cetaceans. Although limited to a skull, the Pakicetus fossil provides precious details on the origins of cetaceans. The skull is cetacean-like but its jawbones lack the enlarged space that is filled with fat or oil and used for receiving underwater sound in modern whales. Pakicetus probably detected sound through the ear opening as in land mammals. The skull also lacks a blowhole, another cetacean adaptation for diving. Other features, however, show experts that Pakicetus is a transitional form between a group of extinct flesh-eating mammals, the mesonychids, and cetaceans. It has been suggested that Pakicetus fed on fish in shallow water and was not yet adapted for life in the open ocean. It probably bred and gave birth on land. 【OG- The Origins of Cetaceans】
3. The word “precious” in the passage is closest in meaning to
1.precious [ˈpreʃəs] adj.贵重的；珍贵的
TOEFL例句：Every town wanted one; conquerors seized them as especially precious spoils of war; tourists came to see and hear these machines the way they made pilgrimages to sacred relics.——TPO-30: The Invention of the Mechanical Clock
GRE例句：The 1973 Endangered Species Act made into legal policy the concept that endangered species of wildlife are precious as part of a natural ecosystem.——GRE 1998年11月题,Section B
preci=price，如“appreciate”（赏识）（TPO-11: Ancient Egyptian Sculpture）
-ous*形容词后缀，表示“充满了”，如“advantageous”（有利的；有益的）（TPO-11: Begging by Nestlings）
2.precious 英 [ˈpreʃəs]美 [ˈprɛʃəs]
1).ADJ-GRADED 宝贵的；珍贵的；贵重的 If you say that something such as a resource is precious, you mean that it is valuable and should not be wasted or used badly.
例句：After four months in foreign parts, every hour at home was precious...在国外呆了4个月后，在家的每一刻都是宝贵的。
2).ADJ-GRADED 珍奇的；珍稀的 Precious objects and materials are worth a lot of money because they are rare.
例句：...jewellery and precious objects belonging to her mother.她妈妈的珠宝和珍奇物品
3).ADJ-GRADED 值得珍视的；可贵的；重要的 If something is precious to you, you regard it as important and do not want to lose it.
例句：Her family's support is particularly precious to Josie...家庭的支持对乔茜来说尤为可贵。
4).ADJ 宝贝似的（强调对别人珍视的东西表示厌恶） People sometimes use precious to emphasize their dislike for things which other people think are important.
例句：You don't care about anything but yourself and your precious face.你什么都不关心，除了你自己和你那张娇贵的脸。
5).ADJ-GRADED 矫揉造作的；一本正经的 If you describe someone as precious, you mean that they behave in a formal and unnatural way.
例句：Actors, he decided, were too precious and neurotic.他认定演员们太做作，并且都神经兮兮的。
6).PHRASE 一点点；极少 If you say that there is precious little of something, you are emphasizing that there is very little of it, and that it would be better if there were more. Precious few has a similar meaning.
例句：The banks have had precious little to celebrate recently...银行最近没几件值得庆贺的事。