question about a sentence
It was much more complex than that. In the spring of 1963, when Ruth was seeing a great deal of the Oswalds, she observed that they were always "arguing and bitching at each other, and neither seemed to know what to do about it." Actually, Marina was the better fighter. She knew his weaknesses, and she was a quick girl with a knee. Eventually it was Lee who capitulated, Lee who allowed her to shut him in a bathroom as punishment, Lee who sank to his knees in the dark and wept bitterly as the greater darkness of his private nightmare enveloped him.]

does "she was a quick girl with a knee" have any special meaning?

Question

question about a sentence
 It was much more complex than that. In the spring of 1963, when Ruth was seeing a great deal of the Oswalds, she observed that they were always "arguing and bitching at each other, and neither seemed to know what to do about it." Actually, Marina was the better fighter. She knew his weaknesses, and she was a quick girl with a knee. Eventually it was Lee who capitulated, Lee who allowed her to shut him in a bathroom as punishment, Lee who sank to his knees in the dark and wept bitterly as the greater darkness of his private nightmare enveloped him.]

does "she was a quick girl with a knee" have any special meaning?

Answer

It means that Marina was able to move her legs fast so as to be able to strike Lee with her knee.  Although it is unstated, I read into it that Marina would kick Lee in the groin.

Answer

it means she could knee someone quickly.

to knee someone means to hit them with your knee. in that case knee is used as a verb rather than a noun.

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