"Please don't say something that will ruin my concentration, Sir Canillas," Joanna retorted while trying to place her concentration back on track so that she would not miss her steps, which would only humiliate not only herself but also the man who had led her well until now.
She was indeed amazed at his surprising talent, but she could not tell him that, as if she did, she somehow had a sense that they would indulge in prolonged conversation that would then take the whole of her concentration on the topic they were talking about. Because she was not as good as him at dancing.
She needed to keep her focus intact, pushing aside all her curiosity, which would become one of the reasons why she had a sense that the conversation would take more time than necessary.