It is so weak, That a little wind can move it, it is so strong, That you cut it with a knife and leave no trace. What is it?

它如此脆弱，微弱的风也能吹动它，然而它又如此强壮，用小刀切割它也不会留下一切印记，它是什么？

youdao

What can you see when there is a strong wind?

当有大风的时候你能看见什么？

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What can you see when there is a strong wind?

当有大风的时候你能看见什么？

youdao