But as she was dancing the last quadrille with one of the tiresome young men whom she could not refuse, she chanced to be vis-à-vis with Vronsky and Anna. She had not been near Anna again since the beginning of the evening, and now again she saw her suddenly quite new and surprising. She saw in her the signs of that excitement of success she knew so well in herself; she saw that she was intoxicated with the delighted admiration she was exciting. She knew that feeling and knew its signs, and saw them in Anna; saw the quivering, flashing light in her eyes, and the smile of happiness and excitement unconsciously playing on her lips, and the deliberate grace, precision, and lightness of her movements.
"Who?" she asked herself. "All or one?" And not assisting the harassed young man she was dancing with in the conversation, the thread of which he had lost and could not pick up again, she obeyed with external liveliness the peremptory shouts of Korsunsky starting them all into the grand rond and then into the châine, and at the same time she kept watch with a growing pang at her heart. "No, it's not the admiration of the crowd has intoxicated her, but the adoration of one. And that one? can it be he?" Every time he spoke to Anna the joyous light flashed into her eyes, and the smile of happiness curved her red lips. She seemed to make an effort to control herself, to try not to show these signs of delight, but they came out on her face of themselves. "But what of him?" Kitty looked at him and was filled with terror. What was pictured so clearly to Kitty in the mirror of Anna's face she saw in him. What had become of his always self-possessed resolute manner, and the carelessly serene expression of his face? Now every time he turned to her, he bent his head, as though he would have fallen at her feet, and in his eyes there was nothing but humble submission and dread. "I would not offend you," his eyes seemed every time to be saying, "but I want to save myself, and I don't know how." On his face was a look such as Kitty had never seen before.
They were speaking of common acquaintances, keeping up the most trivial conversation, but to Kitty it seemed that every word they said was determining their fate and hers. And strange it was that they were actually talking of how absurd Ivan Ivanovitch was with his French, and how the Eletsky girl might have made a better match, yet these words had all the while consequence for them, and they were feeling just as Kitty did. (1.23.1-4)
Kitty deduces with horror that Vronsky and Anna are falling in love, and this happens without any need to put their attraction into words. Their shared emotion overflows into their ordinary, dull conversation.