The explanation may be in Earth's mantle, the layer of rock underlying the tectonic plates and extending down over 1,800 miles to the outer edge of Earth's iron core.

解释可能是在地球的地幔中，这是在构造板块下面的岩石层，向下延伸超过1800英里到地球铁芯的外边缘。

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This arrangement makes it possible to bubble the exhaust gas down through the outer compartment and then bubble it back up through the opaque middle.

这种安排使得它可以导引废气穿过外隔层，然后再导引其经由中间的不透明管道返回。

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Then, solemnly, the group walked down an outdoor,semi-covered wooden corridor and up a short flight of steps, onto the platformof a large outer shrine.

接着，代表团神色严肃的走出屋，穿过半遮蔽式的木质走廊，借一小段楼梯来到了神殿外的广场。

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An up-and-comer who's now a down- and-outer. Do you remember that scene in the back of the car with his brother Charlie a small time racket guy?

VOA: special.2009.11.30

Rather than being forced to re-inject the patient, the outer cannula moves up and down to locate the position, with a thinner curved stylet extends from within it, reaching the designated area.

ENGADGET: Robotically Steerable Probe aims at minimally invasive surgery, moves through gelatin like a champ

The two placed a pair of gloves down on center ice, and Mr. Martin executed tight, figure-eight turns while shifting weight between inside and outer skates.

WSJ: What's Your Workout? A Skater's Edge