I didn't sleep all night yesterday, and when I finally felt sleepy, this aunt and grandmother came again, to be honest, Xie An's heart was dead.

But then again, he didn't dare to offend the woman in front of him, so he had to brace himself and explain to her what he had said in the carriage that day.

"First of all, you have to understand the concept of [appreciation], what I told you in the carriage that day was something that was well known to me, so it is called common sense ......."

"Where are you?" Eldest Sun Xiangyu obviously caught the loophole in Xie An's words, frowned and asked, "Didn't you say that you were from Guangling?" ”

"......" Xie An, who was interrupted, opened his mouth and looked at the eldest grandson Xiangyu angrily, right now, to be honest, he didn't even have the energy to justify.

Looking at Xie An's expression, the eldest grandson Xiangyu pouted and said, "Okay, good, you say, I just don't intervene!" ”

Shaking his head helplessly, Xie An said concludingly, "In short, appreciation, you can understand it as the most basic knowledge, and what I am going to tell you next is within this category......" As he spoke, he thought for a while and said in a deep voice, "In this way, let's talk about the concept of [heaven and earth] today......"

"What's there to say?" The eldest grandson Xiangyu sat on the chair next to the desk with his chin propped up, and said with a look of interest, "The sky above my head is the sky, and the ground is under my feet......"

"......" looked at the eldest grandson Xiangyu speechlessly for a long time, Xie Jian didn't hear it, and said to himself, "Ancient people only had a very general concept of heaven and earth, they thought that the sky was round, the earth was square, the sky covered the earth, the earth was raised by four pillars, and even made up some mythological stories......"

"I know that...... Well, I won't interject! ”

"In short, the concept of [the heaven is round and the place is round] is wrong," Xie An said, raised his hand and picked up the brush, drew a circle in the flat paper on the desk, and then pointed to the side of the circle, and explained in a deep voice, "The ground under our feet, it is actually a circle, more precisely, it should be a ball, so in our place, we call the ground under our feet [earth]!" ”

"It's so ugly...... No, you mean, it's like the daughter's family used to play with hydrangea? Seeing Xie An's unswerving expression, the eldest grandson Xiangyu hurriedly changed his words halfway and asked curiously.

The hydrangea she refers to, Xie An has also seen, is a kind of ball made of fine bamboo silk and grass reeds, specially for children to play, if it is more delicately made, the outside is also wrapped in animal fur, a bit similar to the ancient juju, but smaller than that, lighter, basically for children to throw balls to play.

“…… It's about the same shape, but it's bigger, much bigger, bigger than you think! ”

"You mean, we're all standing on the same ball?" Glancing at Xie An suspiciously, the eldest grandson Xiangyu frowned slightly, and suddenly pointed to the circle in the painting and asked, "Even if you can stand on the top, how can you stand on the left and right sides and below?" ”

"Wrong! For this ball, there is no real sense of up and down, it is a moving sphere, just like this," said Xie An, holding down the center of the circle in the painting with his left index finger, and moving the edge with his right hand slightly to make the circle in the painting rotate slowly.

"But even if that's the case, the people on the left and right sides and the bottom side will still fall......"

Xie An shook his head when he heard this, he knew that this woman had misunderstood, so he took a pen and drew four villains on the circle in the painting, all with their feet next to the edge of the circle.

"That's it!" Xie An explained with a gesture, but he didn't expect the eldest grandson Xiangyu to look at the four strange-looking people in the painting, and couldn't help laughing.

“…… I'm so sorry I draw so ugly! Looking at her covering her face with a folding fan, and her delicate body trembled slightly with a smile, Xie An was angry.

Perhaps noticing that Xie An's face was getting worse and worse, the eldest grandson Xiangyu stopped laughing and said flatteringly, "Okay, okay, don't be angry...... But isn't it even more strange that you draw like this? ”

“…… You're right, under normal circumstances, it is really impossible to stand like this, but the ground under our feet has a gravitational force called gravity, which starts from the center of the circle and acts perpendicular to the edge of the circle......"

"[Gravity]? What is that? The eldest grandson Xiangyu asked in wonder.

Xie An didn't answer when he heard this, he picked up a brand new piece of paper from the table, grouped it up one by one, and then shook it in front of the eldest grandson Xiangyu's eyes, threw it vertically, and finally, when the paper ball reached the highest point and began to fall, he took it in his hand.

"Tell me, why did I throw it up, but this ball of paper ended up falling again?"

The eldest grandson Xiangyu is not an ordinary woman after all, after some deep thought, he understood what Xie An wanted to express, and asked hesitantly, "You mean, what gravity is this because of?" ”

"Not bad! It is precisely because of this gravity that we can stand firmly on the edge of this circle, whether it is up and down, left and right......"

"That's really ...... Fantastic! -- How can you prove that what you say is correct? The look in the eyes of the eldest grandson Xiangyu gradually became rigorous and serious.

Looking at her serious and studious expression, for some reason, Xie An didn't feel sleepy for a while, and enthusiastically explained to her the rotation and revolution of the earth, as well as the reasons for the formation of the four seasons of the year.

From beginning to end, the eldest grandson Xiangyu was like a diligent and studious Qianqian student, absorbing the knowledge that Xie An told her.

The speed she mastered was really amazing, and even in the end, she was able to answer the questions raised by Xie An by drawing inferences, although those questions were relatively simple, but for her who had never been involved in this aspect of things, it was already a very remarkable thing.

I have to admit that a smart student can often stimulate a person's interest in teaching, and Xie An is the same at this moment.

At first, he didn't have much interest in telling the so-called common sense for the eldest grandson Xiangyu, but as he spoke, he gradually became a little interested, maybe he also wanted to take a look, to see if the wise and almost demonic woman in front of him could understand his knowledge that surpassed this Great Zhou for at least a thousand years.

“…… Rainfall, this is a process, in general, first the water in lakes, rivers, and even the sea evaporates, turns into water vapor and rises to mid-air, and the dust in the clouds in the mid-air halo condenses to form crystals, and when the crystals condense to a certain scale, they will become water droplets, which fall under the influence of gravity, which is also the phenomenon of rainfall...... However, the clouds above it is not fixed in one place, it will be affected by the wind, air currents, thus changing the position, for example, the rain clouds formed in Jijing do not necessarily cause rain in Jijing, if the rain clouds drift to other places, it will form rain in other places......"

"......I see," the folding fan in the hand of the eldest grandson Xiangyu snapped away, looked at Xie An and frowned, "No wonder a few years ago, Hanoi and other places along the Yellow River would have such a drought, and there would be no rain for dozens of days......"

"Clever! -- But that's just a special case, and to put it simply, when rain clouds are formed, there happens to be a strong wind, which blows the rain clouds that have not yet formed rain...... It doesn't happen much, it's not so much that the rain clouds blow away and cause a severe drought in Hanoi, but that the distribution of water in Hanoi is problematic itself......"

"Something?"

"Ahh It may be that the trees are cut down too frequently, so that the water vapor rising in the area is insufficient to cause rainfall, or it may be that the upstream of some rivers has been cut off and the waterways have changed, so that some rivers that originally passed through the river have changed their direction, so that the downstream lakes are not replenished by water and gradually dry up...... Lakes and rivers dry up, the rising water vapor is insufficient, and it is naturally difficult to form rainfall, and this vicious circle leads to the eventual outbreak of drought ......"

"......" Eldest Sun Xiangyu listened quietly, and after waiting for Xie An to finish speaking, he muttered, "Do you mean that if you can widen the upstream river channel and let it continue to flow in its original direction, you can eradicate the drought?" ”

"It can only be said that the occurrence of drought is reduced, not completely eradicated!" Xie An reminded emphatically.

The eldest grandson Xiangyu closed her eyes and recalled all kinds of [common sense] that Xie An had just said, and only opened her eyes again after half a ring, she looked at Xie An's gaze, which was very different from what she thought a few days ago.

"I've never heard of what you're talking about......" As she spoke, she slowly sat up straight, looked at Xie An, and said with a smile, "Now, Xie An, can you teach me everything you know?" ”

Looking at her expression of interest, Xie An laughed, pouted and said, "Why should I teach you?" - Give me a reason! ”

"Well, what you're talking about is much more interesting than calculating other people's boredom...... If you teach me, I won't have to calculate others to relieve my boredom in the future......"

"It's my business!" Xie An couldn't smile bitterly when he heard this.

"Doesn't count?" The eldest grandson Xiangyu blinked, leaned over, and smiled sweetly, only to laugh Xie An creepily.

"In short, what I want to get, I have never missed, instead of forcing you to comply, I advise you to obediently accept me as a student, and honestly teach me everything you know, as for the reward, I can use the power of my grandfather and my eldest grandson's family to prevent His Royal Highness the Crown Prince from tracking down the person who attacked him that day......"

"What? - You said that the prince would investigate the matter again? Xie An was shocked when he heard this.

"You seem surprised?" The eldest grandson Xiangyu shook his head with a smile and sneered, "Don't forget, you ruined his good deeds, do you think he will let you go easily?" If he finds out, you knocked him unconscious that day and turned Sister Wu into his own woman, with the character of His Royal Highness the Prince, he will never let you go! ――How? Did you come to want to accept a student called the little girl a little? ”

"You are really ......" Looking at the smiling face of the eldest grandson Xiangyu, Xie An exhaled helplessly, and was about to speak, when suddenly his heart moved, he looked at the woman in front of him and frowned and said, "You knew that the prince was sending someone to investigate that matter?" ”

"That's right!"

"But you didn't say a word about it before...... Can I understand that if what I say does not interest you, you will deliberately reveal the truth of that matter to the prince, and then hide and watch the show as before? ”

"Huh?" The eldest grandson Xiangyu looked at Xie An in surprise, and there was an inscrutable smile on the corner of her mouth, which made Xie An feel cold on his back.

Hey, hey......

This woman is really too dangerous!

Perhaps noticing Xie An's vaguely jealous gaze, the eldest grandson Xiangyu got up and walked to the round table in the center of the outhouse, poured a cup of tea, and then handed it to Xie An with a tea cup in both hands, and giggled, "It's really a little family, aren't you okay, you see, people will pour water for you to drink...... Don't worry, you are very interested in what the slave family said today [common sense], and the slave family will not harm you......"

"It won't hurt me until you hollow out everything I know, right?" Taking the teacup, Xie An said with a sneer.

"Don't say it so explicitly, it's a shameful ......" Eldest Sun Xiangyu chuckled, slowly raised his right hand, and gently touched Xie An's lips with his slender index finger, then leaned down and laughed in a low voice, "But on the other hand, if you can always make the slave family interested in you, won't it be fine?" - The prince's place, the slave family will help you cover up as much as possible......" As she spoke, she lowered her right hand and gently dragged Xie An's hand holding the teacup.

I have to say that that little hand is indeed soft and white, which makes Xie An's heart a little budding, but it is a pity that the owner of this little hand is such a scheming woman who is afraid that the world will not be chaotic.

However, with something to teach her, she should be a little more well-behaved......

Thinking of this, Xie An licked his lips and drank the bowl of tea in his hand in one gulp, after all, after talking for so long, he was also a little thirsty.

Suddenly, Xie An seemed to notice something, his eyes widened, he looked down at the tea bowl in his hand in disbelief, and asked in a trembling tone, "You...... What did you pour for me? ”

The eldest grandson Xiangyu, who was still sitting sideways in the corner of the desk, showed a little puzzled, turned over slightly, pointed to the clay pot on the round table not far away with the folding fan in his hand, and said with an inexplicable expression, "It's in that jar, isn't it the cold warming tea prepared by the chef in the house?" I look at the ...... that is quite rich."

Hearing this, Xie An subconsciously raised his head and looked at the familiar crockpot in amazement.

"I'll go!"