After Wenren Sheng finished handling matters and returned, Little Illusion latched onto him.
"Dad, how did you do that just now? Teach me already!" She hung from Wenren Sheng's thigh and swayed, perfectly playing the role of an accessory.
Well then, she called him Dad when she needed something, and Old Wen when she did not...
Wenren Sheng rolled his eyes. "It's a very advanced technique, involving the application of many laws of time and space... You need to study knowledge of time and space."
"Oh, knowledge of time and space. Is this it?" As she spoke, Little Illusion conjured a textbook in her hand: "Third-Grade Elementary Mathematics—Part 2."
Her little hands quickly flipped to the two units on "Area" and "Timekeeping."
"Yes, that's it. Study it carefully." Wenren Sheng nodded very seriously.
"Fine. Once I've learned it inside out, you have to teach me." Little Illusion lowered her head and began reading.
"Definitely."
Wenren Sheng nodded.
Half an hour later, Little Illusion shouted, "I've learned it! The area of a rectangle is length * width, and the area of a square is side length * side length. The conversion rate between area units is 100, and there are twelve-hour and twenty-four-hour timekeeping systems."
"Yes, you learned very well." Wenren Sheng smiled and took the book. "But I need to test you with a few questions."
"Test away, test away. I definitely won't get burnt." Little Illusion said confidently.
"You now know that the area of a rectangle is length * width, L * W. It can be viewed as W Ls added together."
"Good. Now calculate the area of this closed figure. Three curves and one straight line intersect respectively, forming a closed figure. The functions of the three curves are... and the function of the straight line is...