"Tongtong, your dad and I will go home first!"

Teacher Jin had no worries about leaving the child at her parents' home. The child had grown up there, and was as familiar with the place as at home, and even more doted on.

Tongtong has been studying hard this month, and it's a good opportunity for her to relax at her grandfather's house.

Wu Tong waved goodbye to her parents. She was staying at her grandmother's house for two days, and it would only take half an hour to go home, so there was no need to be reluctant to leave.

After sending Jin Yu and his wife away, Jin Yongning instructed his son to take Wu Tong's reference books upstairs, and then happily invited his eldest granddaughter to eat watermelon. Holding a small watermelon in both hands, removing the top and using a small spoon, Wu Tong was treated like a spoiled child in the Jin family.

After eating the melon, my aunt took Wu Tong to try on the new clothes she bought for her.

Xu Meifeng has a keen eye for fashion and the clothes she buys are just right for Wu Tong's age. The light yellow, willow green, and cherry blossom pink are all bright colors that represent youth.

In Wu Tong's future memories, she hadn't worn such delicate colors in years. After work, white, gray, black, and blue became her primary colors. Reliving these youthful colors, Wu Tong smiled and realized that she was still young, so what color couldn't she wear? She cherished her youth.

Wu Tong held her aunt's arm and gave her a thumbs-up of thanks and praise, which made Xu Meifeng hug Wu Tong and smile from ear to ear. Raising a little girl is really a joy. She looks beautiful no matter how she dresses!

Her brat, who was passable when he was young, is now so rough he can't even describe it! His clothes change with the seasons. He buys a few sets of clothes from the same store. The styles are similar, but they are simple and convenient. There is no room for her to express herself. She is not as fashionable as the child's father.

After spending some time with his family, Wu Tong sat down at his desk again. It was already four o'clock.

From Jin Xin's bookshelf, Wu Tong took out a book of required math exercises for the second year of high school, read only the questions, and covered up the answers that Jin Xin had done. He then used a piece of scratch paper to do the exercises again. For some of the exercises that Jin Xin had not done, Wu Tong simply added the answers.

Can we say they are worthy of being brother and sister? The reference books all have the same problem: most of them are about sleeping.

"Hey, Tongtong, are you serious?" Jin Xin, following her mother's instructions, came up to call Wu Tong for dinner. Upon entering, she saw Wu Tong working on his homework again, without a trace of pretense. She couldn't help but ask cautiously, "Are you serious?"

He hurried back to have dinner as he had to go back to school for evening self-study.

The Jin family's meal times now follow Jin Xin's schedule. They start eating when Jin Xin comes home, and the meal time is quite standard.

"Of course, when have I ever joked about this?"

···Therefore, quadrilateral EFGH is a parallelogram.

Wu Tong put down the finishing touches on the geometric proof in his hand, raised his eyebrows and nodded seriously.

"My sister is better than my brother!" Jin Xin gave a thumbs up. He really felt Wu Tong's seriousness.

If Tongtong really wants to get in, I'm not kidding, he still has that kind of energy.

It was only when he entered his third year of high school that he began to learn to control himself, focus, and strive for the college entrance examination. With more and more college students now, he wanted to get a college degree, so that he could show it off in the future, right?

Supporting your sister can also make you feel more confident.

"Here, brother, I support you with my actions!" Jin Xin took out the math textbooks from the fifth compulsory course in high school from the schoolbag in his hand.

At noon, he saw Wu Tong preparing for his sophomore math class. Regardless of the reason, Tong Tong had already prepared, and as his older brother, he felt obliged to help him prepare thoroughly. So, after school, he immediately gathered all the math textbooks from sophomore year onwards into his schoolbag and brought them back to Wu Tong.

"Brother, you should be using it for your review now, right?" Wu Tong didn't want to affect Jin Xin's review. Every moment of senior year was precious.

Jin Xin smiled coolly and waved his hand, "Don't worry, little girl. We've just started the second round of review. We won't need these textbooks in the next few days. Even if we do need them, Shitou and I can just share one!"

Tongtong’s new books will be distributed at the beginning of the school year, in three to five days at most. What’s the point of delay?

"Use whatever you want, don't be polite to me!"

Wu Tong knew that Shi Tou was Zhao Lei, the little brother's deskmate and also his childhood friend. The two of them were so close that they could wear the same pants.

"Okay, then lend me these textbooks for two days!" Wu Tong nodded. One textbook is required and three are electives. This is the last textbook for the entire high school mathematics. If she works hard, she will be able to return the books to the boy by the next morning at the latest.

···

Jin Xin thought that the two days Wu Tong mentioned was just a quantifier, referring to the few days before school started. He never expected that Wu Tong really spent less than two days to go through these textbooks in depth.

When Wu Tong returned the textbook to him early the next morning before morning reading at school, saying that he had finished learning it all, Jin Xin thought he was still sleepy.

Just read through them all?

"Tongtong, I'm really not in a hurry to use it!" Jin Xin scratched his head, his sleepy face still looking confused.

"I have really finished learning it. I have added some notes for you, and I hope it can be helpful to you. If you have any questions, you can come to me for tutoring at any time!" Wu Tong smiled brightly, as if he was about to accidentally irritate the boy. How embarrassing!

"Brother, it's only a gift to return the favor. These are the mock exam papers that you don't have yet. I think the questions are pretty good. Take them and practice with them. No need to thank me!" There are two copies, and she will finish her copy as soon as possible in the next two days. The tutor was not just talking nonsense, but was really capable of doing it.

In the past two days, she not only carefully mastered the knowledge points in the mathematics textbooks for the second and third years of high school, but also spent a midnight to integrate the entire high school mathematics knowledge points and sorted out a knowledge tree for high school mathematics.

Sets belong to sets, functions belong to functions, and series belong to series... The branches and trunks are distinct, and the veins are clear. The entire high school mathematics formula is in Wu Tong's mind, and he has a further sublimated experience.

Her mathematical knowledge knife has been sharpened to an extremely sharp level. Starting today, she will tackle all high school math problems.

Jin Xin couldn't believe it and flipped through the textbooks in his hands quickly. In each of the four math textbooks, there was one or two draft papers with densely written notes in each chapter. They were all analyses of the important knowledge points in each chapter and the derivation and analysis of the formulas.

He couldn't even imagine the scale of such a project!

He casually glanced at the notes on the chapter of trigonometric geometry that he mastered best, and saw that the formula derivation and analysis in the neatly written notes were rigorous, correct, clear and detailed, just like the teacher's explanation and analysis!

Such verification results made Jin Xin even more shocked. At the same time, it also proved that the little girl was not lying at all and had truly finished learning the four math books in her second and third year of high school!

Jin Xin was stunned. After sixteen years, he was so short-sighted that he only realized today that his sister was a super genius?

Mastering all the math for Grade 12 and Grade 13 in just two days? This is unbearable! !