This not only forces you to clean up the source nodes that are left behind, but it can also be expensive if the subtree you're moving is large.

这不仅要求清除留在后面的源节点，而且当要移动的子树很大时需要付出很高的代价。

youdao

You don't run the risk of being left behind by taking a conservative stance at this point.

此时此刻，你不会为作为一个保守者而承担任何风险。

youdao

You can see some of the damages left behind in this i-report video.

你可以在这个《我报告》的视频中看到台风过境后的一些损害。

youdao

This is what you see here: a large pool of water left behind by the sea.

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At this point, the only color you see are the occasional yellow footprints the swan has left behind useful for tracking the crafty Cygnus plus the occasional yellow letter suspended seemingly in mid-air.

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