微小的拇翼改善了对飞行的控制能力，第一翼羽上的凸出轴结构会发出沙沙的响声——在保持视觉效果的同时还增添了声学效果。

A tiny feathered "thumb," the alula, improves flight control. The protruding shaft on the first wing feather makes a loud, rustling sound—adding acoustics to the visual display.

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微小的拇翼改善了对飞行的控制能力，第一翼羽上的凸出轴结构会发出沙沙的响声——在保持视觉效果的同时还增添了声学效果。

The protruding shaft on the first wing feather makes a loud, rustling sound—adding acoustics to the visual display. At Peabody Museum of Natural History, Yale University

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微小的拇翼改善了对飞行的控制能力，第一翼羽上的凸出轴结构会发出沙沙的响声——在保持视觉效果的同时还增添了声学效果。

A tiny feathered "thumb," the alula, improves flight control. The protruding shaft on the first wing feather makes a loud, rustling sound-adding acoustics to the visual display.

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因为其前后肢上都存在着较长的羽翮，因此徐星将它称之为“四翼”恐龙。

Xu calls it a "four-winged" dinosaur because it had long, pennaceous feathers on its arms and legs.

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兽脚亚目食肉恐龙是早期的有翼和羽的恐龙，其主要靠后足行走且不会飞行。

Theropods were early winged and feathered dinosaurs that walked mainly on their hind legs and were incapable of flight.

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翼上初级飞羽呈现灰白色，翼前缘经常为淡棕色或黄棕色，比飞羽的深灰色要浅。

Upperwing has pale greyish-white primary bases and often pale rufous or yellowish-brown forewing, paler than dark grey flight-feathers.

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翼上初级飞羽呈现灰白色，翼前缘经常为淡棕色或黄棕色，比飞羽的深灰色要浅。

Upperwing has pale greyish-white primary bases and often pale rufous or yellowish-brown forewing, paler than dark grey flight-feathers.

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