Jiang Mianmian looked at his amiable face, thought for a moment, and decided to tell the truth, "Teacher Liu, actually I've already studied all those problems you talked about in advance."
"What? You've studied them all?" Teacher Liu was somewhat surprised to hear Jiang Mianmian say this.
"Yes, Teacher Liu, I have already studied them."
Teacher Liu's first reaction was disbelief, but then she thought of how Jiang Mianmian had completed three grades' textbooks in just two short months and somehow felt it was very plausible.
So, after thinking it over, she said, "Then let me test you."
As she spoke, she turned a few more pages in the textbook and wrote several typical math problems on a sheet of white paper, handing it to her.
"Okay." Jiang Mianmian took it, picked up the pen, and finished writing in just a few minutes.
Teacher Liu watched her problem-solving process with a surprise; she had indeed brought a genius into her class.