With upper body straight, hold for a few seconds and move it to the side; hold and extend it behind you.

上身要挺直，坚持几秒钟，然后换个脚。

youdao

The entry into water shall in all cases be vertical with the body straight, the feet together and the toes pointed.

所有的入水动作都是身体笔直并与水面垂直，两腿并拢，脚趾用力伸直。

youdao

Allow the leg to stretch down to the ground, but keep your body straight. You could add ankle weights to help the stretch.

脚可以伸展触地，但要保持你的身体笔直。你可以在踝关节加重来帮助伸展运动。

youdao

One way to say it is, every body will continue to remain in a state of rest or uniform motion in a straight line.

另外一种说法是,任何物体都会继续保持静止,或匀速直线运动的状态

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He instructs runners to keep a straight upper body and a "crunch" going in their lower abdominal muscles.

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The new vaccine microspheres, on the other hand, can be injected straight into the body, eliminating those sorts of mistake and with them the need for the preservatives found in ordinary vaccines.

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