The front and back leg quadriceps contract, extending the knees and stretching the lower region of the hamstrings.

股四头肌前侧和后侧收缩，伸直膝盖、伸展腘旁肌下部。

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Argon bubbles distribute unevenly and the gas holdup of liquid steel in the upper region is far higher than that of the lower region.

氩气的分布不均匀，上回流区钢液的含气率大大高于下回流区。

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In contrast to the city lights along the sea coast and interior, the Atlantic Ocean appears as a featureless dark region filling the lower right quarter of the image.

和海岸线和内陆附近的光亮的城市相比较，大西洋完全漆黑一片，并且占据图片区域的四分之一。

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Pakistani media broadcast footage of thousands of people walking out of the Lower Dir region, fleeing helicopter gunship attacks and artillery strikes against Taliban militants accused of attacking security forces.

VOA: standard.2009.04.27

In September,a power struggle erupted in violence in the lower Juba region between al-Shabab and Hizbul Islam, a clan-based Islamist-nationalist group which had been al-Shabab's main ally in its year-long battle to overthrow the U.N.-backed government in Mogadishu.

VOA: standard.2010.01.02

More than 2, 000 miles of streams are polluted by mine drainage, and smallmouth bass in the lower region are suffering from increasing levels of disease, Swartz said.

WSJ: Susquehanna River commission wants gauge funding

Its pillars include efforts to deepen security partnerships in the region, support democratic reforms in places such as Myanmar, and expand engagement especially with countries in the Lower Mekong region.

WSJ: Southeast Asia Gets a Boost From Clinton

Harry was pierced by shrapnel in the lower abdomen region but survived.

BBC: Somerset - In Profile: Harry Patch