In the days that followed, because Yinzhen went back and forth to Guozijian every day to study, everything in the fourth elder brother's mansion was safe and sound, and nothing happened.

Gu Qinghuan and Yaqi, under the guidance of Mama Zhuang, became more and more comfortable with taking care of the affairs of the house, and everything went smoothly.

At the end of February, the weather is getting warmer. After taking off the winter coat, Gu Qinghuan felt a little refreshed.

In the evening, the porter said that Zhuangzi had sent fresh fruits and vegetables, and Gu Qinghuan hurriedly led Yaqi over for acceptance.

It's all seasonal vegetables and a basket of red cherries.

"There's cherries!"

Aki watched as the servants moved their things into the kitchen, staring straight at the basket of cherries, like a hungry wolf seeing a little sheep, and eager to pounce on it.

"Don't be too obvious..."

Gu Qinghuan hurriedly reminded Yaqi to regain some of her thoughts.

"I know!" Yaqi stuck out her tongue, but she was still salivating at the basket of cherries.

Two quarters of an hour later, all the vegetables and fruits were moved into the kitchen, and Gu Qinghuan went to get a basket of cherries, saying that they would be washed at night and given to the fourth elder brother to eat.

On the edge of the well, Yaqi worked hard to get a bucket of water from it, and accompanied Gu Qing to wash the cherries happily.

"I steal a few, it shouldn't be in the way, right?"

Yaqi looked around, and when she found that there was no one in her mouth, she shoved four or five cherries directly into her mouth.

"It's so sweet!"

Before she could eat the cherries, Yaqi sighed vaguely: "It's good to be the master, you can eat any rare thing." ”

As soon as she finished speaking, Yaqi spit out the cherry seeds, wrapped them in a handkerchief and put them in the palm of her hand.

"Qinghuan."

Yaqi poked Gu Qinghuan and asked, "You said that if I bury these seeds in this soil, will they grow in a few years, so that we don't have to be so bitter." ”

“…”

Gu Qinghuan shook his head and said, "I think... Probably not. ”

"Why?"

Yaqi hurriedly asked, "Isn't this how the seeds are all buried in the soil and then germinated?" ”

"I don't know. But... Probably not. After Gu Qinghuan finished speaking, he tilted his head and remembered a long time ago.

When she was in junior high school, there was a boy who liked her.

She didn't know it herself, but she still heard it from others.

At that time, there was a cherry tree in the school, and when it was fruiting in the spring, the boy ran to secretly pick cherries, only to be found by the dean.

He flew away, and came to her, and gave her little cherry.

Gu Qinghuan was very happy at that time, so happy that he immediately went home and buried the cherries in the soil, hoping that the cherries could take root and sprout and grow into cherry trees, so that they could eat cherries.

While her focus is somewhat different, the... She remembers that the cherries in the soil eventually rotted and did not sprout.

"Won't you be able to eat cherries from now on..."

Yaqi was a little sad when she heard this, and sighed: "Forget it, wait for the next time, and eat a little more." ”

"Hmm."

Gu Qinghuan responded a little dejectedly, so he went to the small kitchen with Yaqi to see what happened to dinner.

On this day, Yinzhen returned home a little late.

Gu Qinghuan was so hungry that he looked at the braised pork that was still hot on the pot, and even had the idea of wanting to eat it himself without waiting for Yinzhen to come back.

But...

Yinzhen is back fortunately.

"Let's set the table." After Su Peisheng finished instructing, Gu Qinghuan and Yaqi hurriedly led the little maids to set up the meal.

In the dining room, Yin Zhen was sitting upright, frowning in a daze. With a straight face, I don't know if it's a bad mood.

Gu Qinghuan suddenly didn't dare to come out, so he just watched from the side.

Fortunately, everything went smoothly when Yinzhen was eating, and nothing went wrong.

When it was dark, Gu Qinghuan had just eaten, and when he passed by Yinzhen's house, he saw Yinzhen reading a book through the half-open window.

He sat at the desk and looked at the books in front of him seriously, like a good student.

"What a hard worker."

Gu Qinghuan thought so, and just as a warm wind blew behind him, he moved the window slightly.

Yin Zhen's thoughts were interrupted a little, and when he was about to close the window, he saw Gu Qinghuan who was standing outside watching him.

"Why are you standing outside?"

Yin Zhen frowned and said, "Come in and help me close the window." ”

“…”

Gu Qinghuan was silent, and said in his heart: "Isn't it faster for you to get up and close the window by yourself than if I go in and help you close the window?" ”

Gu Qinghuan, who was palatable and straightforward, still reluctantly entered the house and helped Yinzhen close the window.

During the whole process, Yinzhen didn't raise her eyelids, she still sat upright, looking at the book in front of her.

Gu Qinghuan was a little curious.

She has also seen Yinzhen reading books, although they are also very serious, but they have never been like now, and they don't turn the pages after reading for a long time.

Finally, driven by curiosity, Gu Qinghuan stretched his neck and glanced at Yinzhen.

With just one glance, Gu Qinghuan was stunned.

Where is Yinzhen reading here! It's obviously a question.

Moreover, it is a math problem.

This math problem is still a geometric body that Gu Qinghuan is very familiar with. The triangles on the diagram converge and look a little messy.

Yin Zhen scratched his ears and cheeks a little, obviously he didn't know how to do it.

The corners of Gu Qinghuan's mouth raised, and suddenly she was in a good mood.

She is not a top student, but she is not bad at math, especially geometry, and she used to get full marks in the past.

"What is the fourth elder brother looking at?"

Gu Qinghuan cautiously spoke up and asked, "What is this?" ”

“…”

Yin Zhen glanced up at Gu Qinghuan, and that look seemed to say, "Don't make trouble." ”

But in a blink of an eye, Yin Zhen seemed to remember something again, and asked, "Will you look at these graphics?" This is the homework assigned by Huang Amma, and it is a proof question. ”

"I remember that you, Amma, were on an errand in Honglu Temple. These geometry problems were transmitted from the West. ”

"Yikes."

Gu Qinghuan pretended to be surprised and said, "No wonder the slave looks so familiar." When he was a child, Amma had nothing to do, and he taught slaves and maids. ”

Yinzhen's eyes flashed slightly, as if he didn't believe it.

Gu Qinghuan came up all of a sudden, pointed to the two straight lines on the diagram and said, "Do you want to prove that this line is equal to the length of this line?" ”

Yin Zhen bowed his head and asked, "Will you?" ”

"Of course!"

As soon as Gu Qinghuan picked up a brush on the table, he began to draw on the paper.

"Make an auxiliary line first, and then prove that the two triangles are equal. And then..."

Gu Qinghuan did it in one go, almost in the blink of an eye, and analyzed this question that had plagued Yinzhen for an afternoon.

PS: Kangxi is indeed a math fan, not only can do geometry problems (including trigonometric functions), but also is proficient in geography.