Ding Xuecheng walked to the side of the small river and saw that the river water was crystal clear, pebbles of various shapes, colors, large and small were lying on the golden sand at the bottom of the water, and there were small fish, small shrimp, sand loach, mussels, snails and so on in the water.

"Observe what?" Is there anything in nature' to see what is in the river? What is a natural phenomenon? It's also 'interesting', alas~ It's good to ask Beibei, but to consume points, reluctantly, Beibei said that the points are of great use, and they must be used by me in the future, and I want to save the points as pocket money. There are too many contents to remember, so it's good to have a paper to write them down. Ask this question: Should I get points? ”

"Beibei, how do those three people write down what they observe?"

"They've all brought notepads, don't worry."

"But I don't have a notepad, why don't I?"

"You don't need a notepad, the light curtain can be used as a notepad, you can silently record what you want to remember, and the light curtain will display what you want to record on the light curtain with text, this function is free of charge, well, don't integrate. However, the light curtain also has the function of taking pictures and videos~"

"Do you need points for taking pictures and videos?"

"Hey~"

"I knew it was like this, how did you act like a vendor?"

"I am very fair and strict, old and young, women and children, children are not bullied, I don't force me to buy and sell, it's all voluntary, don't you spend money on consumption in reality?"

"......, well, I'll write it down, and I'll talk about it when I want to consume it later. By the way, what is a natural phenomenon? ”

"Consume 1 point, Beibei is at your service."

"You! …… I don't get a lot of points~"

"You don't know what a 'natural phenomenon' is, how do you get the job done? Whether or not to serve Beibei is voluntary. ”

"What should I do? Being held by this stingy ghost, it's not okay not to 'bleed'. Okay, you can answer it~"

"Babe will be happy to serve you! Spend 1 point. As soon as Beibei's voice fell, Ding Xuecheng's points on the light curtain were 1 point less, and there were 9 points left.

"Natural phenomena refer to certain conditions in nature that arise spontaneously due to the laws of nature's operation, which are completely unaffected by human subjective initiative. For example, the moon is cloudy and sunny, the four seasons change, the climate is warm and cold, windy and rainy, day and night, etc. There are three main categories: physical phenomena, chemical phenomena, and life phenomena. In contrast to social phenomena caused by humans, natural phenomena do not require human participation and are formed automatically. For example, windy and rainy, foggy and frosty, snow and ice are natural imaginations, but the wind formed by hair dryers, blowers, and people blowing is not a natural phenomenon; In the same way, artificial rainfall, stage smoke, water making popsicles, ice cream, frosting in the refrigerator, etc., are not natural phenomena. Bobo-san, do you understand? ”

"Well, I see, thanks! Ah~ No thanks, I spent points! ”

"Hehe~ Don't be polite, don't be annoyed, you have to give to get, you will understand this truth sooner or later."

"Also, learn and learn, if you don't understand, you have to ask; If you don't ask, you don't understand, and if you ask, there is a price, which is fair, I remember! ”

"Congratulations to Bobo for understanding a philosophy and rewarding 100 points."

"Ahh Can you score points in this way? And so much more! ”

"The philosophy is as profound as the universe, you understand the skin, and the reward of 100 points is not much, keep up the good work~"

Ding Xuecheng was full of joy, feeling that it was too worth spending this point, 1 point for 100 points was secondary, the key was that he vaguely figured out that there are many ways to score, and anyone who understands unknown knowledge will be rewarded, and he will get more in the future......

His expression was straight, silently reciting the "record", thinking about what was in the river in his mind, and the content he thought of appeared synchronously on the light curtain, and lines of text were displayed:

In the river there are: river water, sediment, stones, freshwater fish, aquatic weeds, algae.

The river water is colorless, odorless, clear and transparent, and is a liquid fluid;

The bottom of the river is golden yellow fine sand, and there should be mud and mud underneath;

The yellow sand is covered with pebbles of various shapes and colors, and perhaps emery, ore, and jade;

Sand and stones can be used to make houses and pave roads;

The freshwater fish in the river include small fish, loaches, shrimps, mussels, snails, etc.

Interesting Phenomenon (Question): 1. Where does the river water come from? Why does it flow from high to low? 2. Where did the stones in the river come from? How do you make a round look?

Ding Xuecheng walked to the river to observe and record this, and only more than ten minutes have passed. Seeing that his friends were busy, he had the intention to find a dead branch to find out if there was mud under the yellow sand at the bottom of the river, but he couldn't find it after running around. Thinking of asking for help from Beibei, but the price of "borrowing tools" must be expensive, he hesitated to pay attention to it, and muttered to himself: "It doesn't cost points to ask, and the cost is too great, so I won't investigate." ”

"Beibei, what should you do to find out if there is mud under the yellow sand at the bottom of the river?"

"Beibei provides three sets of solutions for you to choose from: one is drilling and sampling, which consumes 20 points; the second is to dig down with a shovel on the beach and rent a tool for 1 point; The third is to help you drill down, observe directly underground, and consume 100 points. ”

"What? 100 points? You must be looking at my points and bidding! ”

"Let me help you analyze: Plan 2 is directly excluded, can you, who have thin arms and thin legs, dig it down? Maybe you have to dig two or three meters, maybe seven or eight meters, will you dig it? Do you have that strength? I'll rule it out for you. Option 1 is optional, and the cost is small, but the location of the drill has limitations, and it takes multiple drills to get a universal conclusion, which is scientifically important, and if you consume 20 points at a time, your points are only enough to drill 5 times. Plan 3 is the best, spend 100 points at a time, send you underground, carefully observe from shallow to deep, maybe there will be a miracle~ You decide. ”

Ding Xuecheng tilted his head and thought for a long time, hesitated, and said to himself: "Plan 1 is indeed not made by him, so you don't need to think about it; Plan 2 doesn't need to do anything, you can get the result, but Bei Bei said that there are some "limitations", you have to drill a few more times, and in the end you still spend 100 points; Plan 3 seems to be able to carry out underground tourism, thinking about it, I feel that "high, big, up", it must be more exciting than undersea tourism, but it costs 100 points! The 100 points that I just got in my hand are about to fly away if they don't get hot......"

He thought about it again and again, gritted his teeth, and said to himself firmly: "There is a give-and-take!" Fight, maybe there will be a miracle happening~ Beibei, I choose plan three! ”

"Haha~ Bei Bei is willing to serve you, please keep your eyes open and look at it!"

A layer of luminous white light enveloped Ding Xuecheng and sank into the ground like a retreat. Ding Xuecheng was underground, and it was not dark around him, as if he was looking at the wall in a room with a ceiling lamp. The eyes are full of sand and stones, and the further down the stones become, the bigger they become, most of them are round and huge pebbles, like red dates inlaid in rice cakes. The surface of the stone is slippery and slippery, black-brown, yellow-brown, reddish-brown, cyan, gray, black, light white, white...... Further down is the yellow-brown soil, which is nothing to look at, so the light mask wraps Ding Xuecheng and rises slowly.

"Babe, how deep is it now?"

"The river is 12.6 meters below the river, the river is 2.6 meters deep, and now it is 15.2 meters below the surface."

"Stop, stop~ stop! Bebe, what kind of stone is that? Can you put it away? ”

"Yes, the size of the head will cost 1 point, and the size will be increased or decreased as appropriate. Do you want to charge it? ”

"This colored, that yellow, that white, and that black, all collect, ah, that one is so big and beautiful, and it ...... also collected."

"Stop, the points are not enough to collect."

"Can I owe it first and pay you back later? You can borrow it! ”

"No! At this stage, this kind of service is only once, the time is up, go up~"