TPO 1 PASSAGE THE ORIGIN OF CETACEANS

　　这个passage的难度不大，句子的修饰成分、抽象名词并不多。再次挑出6个句子做分析。

　　1) Their streamlined bodies, the absence of hind legs, andthe presence of a fluke1 and blowhole2 cannot disguise their affinities withland dwelling mammals. (抽象名词的使用presence ofsomething)

　　2) However, unlike the cases of sea otters and pinnipeds (seals, sealions, and walruses, whose limbs are functional both on land and at sea), it isnot easy to envision what the first whales looked like. 逻辑的转折成为出题点。

　　3)How was thegap between a walking mammal and a swimming whale bridged? Missing untilrecently were fossils clearly intermediate, or transitional, between landmammals and cetaceans. (missing 前省略的成为对于句子的理解干扰)

　　4)The skull iscetacean-like but its jawbones lack the enlarged space that is filled with fator oil and used for receiving underwater sound in modern whales. (肯定信息和否定信息并列在一个句子中，成为出题点。)

　　5) Many incomplete skeletons were found but they included, for thefirst time in an archaeocyte, a complete hind leg that features a foot withthree tiny toes. (feature 做动词，很难翻译。)

　　6)The structureof the backbone shows, however, that Ambulocetus swam like modern whalesby moving the rear portion of its body up and down, even though a fluke wasmissing.