上龙用四根桨状的四肢推动它庞大的身体在水里游来游去，轻而易举地就能掠食形似海豚的鱼龙。

Using four paddle-like limbs to propel its bulky body through the water, the pliosaur made easy work of passing prey such as dolphin-like ichthyosaurs.

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翼龙的每个前肢都有一根长长的第四指，支撑着像翅膀一样的膜。

In pterosaurs a greatly elongated fourth finger of each forelimb supported a wing-like membrane.

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拖着四根缎带般的硕长尾羽，羽片上还排列着羽支，体型只有鸽子大小的耀龙为我们提供了恐龙利用绚丽羽毛进行展示的最早证据。

Sporting a quartet of long, ribbonlike feathers with barbs arranged in vanes, pigeon-size Epidexipteryx may provide the earliest evidence of a dinosaur flaunting its feathers for display.

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It's from Richard Wagner.

来自理查德，瓦格纳的，尼伯龙根的指环。

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