Imagine a thick piece of rope with a knot in it.

想象一根有结的粗绳子。

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He took a short length of rope and swiftly tied a slip knot.

他拿了一小段绳子迅速打了个活结。

《柯林斯英汉双解大词典》

Pick up the running end of the rope (the end that will be loose after you tie the knot).

拿起绳索的活动末端（在完成绳结后，末端将变得松散）。

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Late on 26 October, he wrote an emotional letter to his US counterpart, President Kennedy, imploring him "not now to pull on the ends of the rope in which you have tied the knot of war".

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