The upper arm is of sufficient length to place the elbow under the highest point of the shoulder.

上臂有充足的长度，使肘部可以正好位于马肩隆下方。

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At that point the fluid-dynamics equivalent of a titanic arm-wrestling match will get under way, with the surface vessels' pumps trying to push the mud down the well while the rising oil tries to push it out.

ECONOMIST: The Gulf oil spill