UNIDENTIFIED MALE: This was the upper surface and this is all still molten, flowing underneath until it all drained away.

这个是上表层，一直在融化，然后在下面流动，直到耗尽干涸。

The upper surface of an airplane's wing is curved, and the bottom surface is flat.

飞机机翼的上表面是弯曲的，而下表面是平坦的。

The pressure across the wing's lower surface is thus higher than that above the upper surface.

因此，机翼下表面的压力高于上表面的压力。

If you can imagine it's red, red hot in here and if the lava just melts the upper surface and causes the cicles.

你可以想象，红色炽热的熔岩流经这里，融化了表层岩体，留下了痕迹。

The formation of this second vortex, again on the upper surface of the wing, provides extra lift for the mosquito.

第二个涡流的形成， 也是在翅膀的上表面，为蚊子提供了额外的升力。

And this is an astragalus or an ankle bone, which has a both an upper and lower curved surface which allows the spring in the step.

这就是一块距骨或者说踝骨，其表面同时有向上和向下的弯曲，使之在走路时有弹性。

If you can imagine, it's red, red hot into and the lava just melts the upper surface that causes the icicles to form.

如果你能想象，它是红色的，炽热的熔岩熔化了导致冰柱形成的上表面。

This increased speed is coupled with a decrease in pressure above the wing, which pulls even more air across the wing's upper surface.

这种增加的速度与机翼上方压力的降低相结合，从而将更多的空气拉过机翼的上表面。

This means that air flowing across the upper surface has a greater distance to travel than the air moving across the lower surface.

这意味着流过上表面的空气比流过下表面的空气具有更大的行进距离。

A wing deflects the air flowing over the upper surface, creating lower pressure above than below, which generates the lift necessary for flight.

机翼使流过上表面的空气偏转，产生上方压力低于下方压力，从而产生飞行所需的升力。

The slow-moving air beneath the wing exerts greater pressure on the wing's lower surface than the fast-moving air exerts on the wing's upper surface.

机翼下方缓慢移动的空气对机翼下表面施加的压力比快速移动的空气对机翼上表面施加的压力更大。

Reckoning the largest sized Sperm Whale's tail to begin at that point of the trunk where it tapers to about the girth of a man, it comprises upon its upper surface alone, an area of at least fifty square feet.

计算体型最大的抹香鲸的尾巴，是从它的躯体逐渐缩小到相当于人腰的地方开始，单是此处上表面的面积就至少有五十平方英尺。