Firstly because running is a single-plane activity – it only uses the body in one direction and uses a limited number of muscle groups at a time.

首先，由于跑步是一种单一水平运动，它只运用了身体的同一方向趋势和在同一时间只活动了有限的肌肉群。

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A single-engine plane took off and banked above the motorway in front of him.

一架单引擎飞机起飞了，倾斜地飞行在他前面的高速公路上空。

《柯林斯英汉双解大词典》

Fat people who are unable to squeeze into a single plane seat will have to pay nearly double to fly with Air France-KLM, the company said Tuesday.

法航-荷航集团19日表示，挤不进一个单人座位的肥胖人士，乘机将付原价的近双倍价钱。

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The 63-year-old Fossett disappeared September 3rd after taking off in a single-engine plane from a Nevada airstrip.

NPR: Annapolis Peace Conference Begins

The golf-course plane, a single-engine Cessna 172, was flying west at an altitude of 3, 500 feet when the second plane, also a Cessna 172, approached from the east after leaving Santa Monica Airport for a test flight.

NPR: 1 Dead After 2 Small Planes Collide Near LA

During World War II, America's P51 Mustang fighter, a single-engine prop plane, creamed the first fleet of German combat jets, the Messerschmitt 262.

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