He waved back, put down the kickstand, and took off his helmet.

他向后挥挥手，放下撑脚架，并脱掉他的头盔。

《柯林斯英汉双解大词典》

In 'come back', 'break down' and 'fall off', 'back', 'down' and 'off' are all adverbial particles.

在come back、break down和fall off中，back、down和off都是副词小词。

《牛津词典》

About half an hour later, I found that he lost a shoe while he was sleeping, I took him off my back and put him down.

大约半小时后，我发现他在睡觉时掉了一只鞋，我把他从背上放下来。

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And when it falls back down that energy is given off.

当它回去的时候,它的能量也消耗殆尽了。

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Bent then came the closest to a home goal all afternoon with a stunning 25-yard free-kick that crashed back down off the bar and to safety.

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It is easy to lose your footing, and tumble back down, bouncing off the steps like the sacrificial victims of a thousand years ago.

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And almost as predictably, China, Russia and some of our European allies will eventually hint that we should back off and sit down and talk without preconditions.

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