Lisa hadn't meant anything by it, she was just like that. If she could, she'd go ahead and start. She thought learning numbers was easy enough, and so she went ahead and did it while they were talking. The moment he began rambling off information about the numbers, she scribbled it all down as fast as she could. When he was finished, she looked up at him with a smile, but he was already backing off and looking quite red. Her smile dropped a bit. Did she smell bad? Did she smell like an old man? Merlin, she knew she would smell like an old man if she stayed here long enough. She leaned closer to try to smell herself without him noticing, hardly hearing him announce that he intended on dictating phrases for her to copy down. She only realized what was going on when she heard him rattling off something in French. Quickly, she reached for a piece of parchment and began writing down what he was saying.
It didn't last long. By time he announced the man's age, Lisa couldn't contain herself. She started to laugh, dropping her quill to put her hand against her mouth. Finally, she looked up at him, stopping herself though still smiling. "Mr. Crotchup, it's a shame you didn't attend Hogwarts," she was still trying to hold back her laughs. "You sounded exactly like one of the professors that taught there. If you had gone to Hogwarts, you would have been so very popular." After a moment, she realized that it probably wasn't right to laugh at an impression of a dead man, and she instantly calmed down. She probably looked completely insane with the way she was laughing, but it had been so long since she really laughed like that. Of course, there was Padma, but she saw her much less often than she would have liked. There was so much laughter built up, it just sort of came out.
"I'm sorry," she said after a moment, smiling apologetically. "I haven't really laughed like that for awhile now."