When Bingley comes to prod Darcy to dance (I love how he says "I hate to see you standing about by yourself in this stupid manner" - it's one of my favorites!)

I presume he's dancing with Jane as he offers to have her introduce Darcy to Elizabeth. I know he's only gone a few moments, but my question is what is Jane (or whomever his partner is, if it is someone else) doing whilst he's conversing with Darcy? It seems that the partner would be standing about in a stupid manner! :) Does she just back out of the line and then rejoin it? I'm confused by this!

Elizabeth Bennet had been obliged, by the scarcity of gentlemen, to sit down for two dances; and during part of that time Mr. Darcy had been standing near enough for her to overhear a conversation between him and Mr. Bingley, who came from the dance for a few minutes, to press his friend to join it.
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