Chapter 227

Xu Da Mao stood at the Siheyuan gate, holding a thick book in his hands, head bowed. Zhao Jianguo had just seen off San Daye and Li Nainai, turned around and saw him.

He was thinner than before, his clothes worn, his face listless, but he stood straight.

"Zhao bro." Xu Da Mao stepped forward, "I'm out, I want to learn some real skills."

As his words fell, Sha Zhu rushed out of the kitchen, still holding a spatula.

"You dare come back?" he shouted, "What you did back then is enough for everyone in the courtyard to remember for a lifetime!"

Someone nearby poked their head out, and children ran over to watch the commotion.

Xu Da Mao didn't dodge or talk back, just held the book tighter.

Zhao Jianguo glanced at him, said nothing, reached out and took the book. The cover was Illustrated Mechanical Principles, the edges worn white, as if it had been flipped through many times.

He opened a page, the paper was a bit thick, the feel off. After flipping a few more pages, he discovered a thin sheet tucked in the middle, which came apart with a light tear.

Inside was hidden a small slip of paper.

Zhao Jianguo showed no reaction, closed the book.

"Do you want to learn?" he asked.

"Really." Xu Da Mao nodded, "I don't expect others to believe me, but I must first believe I can change."

Sha Zhu sneered, "You change? Last time you said you'd change, you turned around and took apart Old Zhang's radio parts and sold them for money!"

Xu Da Mao's face flushed a little, he didn't deny it.

Zhao Jianguo hefted the book in his hand, "Fine, if you want to learn, you can."

Sha Zhu blinked, "You really let him in?"

"But he has to do something first." Zhao Jianguo looked at Xu Da Mao, "There's a name and address in the interlayer of this book. Go find out who this person is, what they do, and where they are now. Three months, give me a solid report."

Xu Da Mao frowned, "Just that simple?"

"Not simple." Zhao Jianguo said, "No using old connections, no lying, no quitting halfway. If I catch you pulling tricks, don't ever mention the word 'study' again."

Xu Da Mao gritted his teeth, "I agree."

Sha Zhu still wanted to stop him, Zhao Jianguo waved his hand, "Let him try. If he fails, he'll leave on his own; if he succeeds, our courtyard will have one more worker."

The crowd slowly dispersed.

Xu Da Mao stood where he was, lowered his gaze to his empty hands, then lifted his head to look at Zhao Jianguo.

"Thanks, Zhao bro." His voice was low but steady.

Zhao Jianguo didn't reply, turned and went inside.

On the table inside lay yesterday's drawn design, the crutch model's circuit board also there. He put the mechanical book in the corner, opened the drawer, took out the communicator.

The screen lit up, a line of prompt popped up:

【Detected residual signal from an overseas intelligence node】

He stared at it for two seconds, then turned it off.

Outside the sun rose high, the courtyard began to buzz with activity.

Xu Da Mao didn't go far, squatted by the courtyard wall flipping that book, while taking notes with a pen on his notebook.

A kid ran over to watch, "Uncle Xu, what are you looking at?"

"Studies." He said.

"Can you learn it?"

"If I can't learn it, I'll just keep learning."

Someone laughed out loud.

He wasn't annoyed, continued to lower his head and write.

In the days that followed, Xu Da Mao left early and returned late every day. By day he went to the Scrap Yard to pick up parts; by night he came back and drew schematics under the desk lamp. Sometimes he soldered circuits, his fingers blistered from the heat, he rinsed them with cool water and kept going.

He also secretly audited the Practical School's class, sitting in the back row, not speaking, just taking notes.

San Daye saw him, blinked, "You're here to listen too?"

"A little is better than none." Xu Da Mao lowered his head, rolling his pen.

"Then you need to shore up the basics first." San Daye handed him a hand-copied Electrical Engineering Introduction, "Start with this."

Xu Da Mao took it with both hands, as if receiving an award.

One month later, he found Zhao Jianguo.

"K-7 is not a person." He said, "It's a code name, formerly used as a mailbox for sending materials, long discontinued. Postal records show the last use was three years ago, when two old books were mailed back to the country; the recipient has since died."

Zhao Jianguo asked, "How did you find out?"

"I made five trips to the Post Office, asking retired workers." Xu Da Mao produced a stack of photocopies, "There are also surveillance screenshots, blurry, but I recognized the back of the person picking up the parcel—it was his son, who later burned the package."

Zhao Jianguo flipped through the materials, nodded.

"Continue."

Another month passed, Xu Da Mao handed in the second report. This time he attached a recording, made at the Archive of a staff member's oral account: that organization had been deregistered ten years ago, all members were on file, nobody remained active.

Zhao Jianguo finished reading, put the materials away in the drawer.

That night, Xu Da Mao returned to his lodgings, found a letter slipped into the door gap.

He took it out and saw no signature, only a few words: "Don't investigate further."

He didn't toss it, didn't panic, took the letter straight to Zhao Jianguo's home.

Zhao Jianguo was calibrating a sensor.

"Someone warned you?" he asked.

"Hmm."

"Who do you think it is?"

"I don't know. But I'm certain this has stirred up someone."

Zhao Jianguo took the letter, shone a light on it, smelled it, "It's not a threat, it's a reminder. They don't want you to keep digging, which shows you're on the right path."

Xu Da Mao inhaled, "Then I'll continue."

"Of course." Zhao Jianguo looked up at him, "It's only been two months; you said three months."

Xu Da Mao smiled slightly, "I want to prove myself sooner."

In the final month he almost never left the house. The rooms were piled with parts, the desk covered with sketches. He designed a machine that could automatically sort scrap metal, plastic and paper shells, using simple Optical Recognition and Weight Sensing.

On the test day Zhao Jianguo took San Daye and Li Nainai to watch.

The machine was placed in the center of the Courtyard and powered on.

Xu Da Mao pressed the switch.

The conveyor belt turned, a pile of junk was dumped in. Metal blocks slid to the left chute, plastic bottles rolled into the middle bin, paper was blown by wind into the right frame.

San Daye leaned in, "The sorting is quite accurate."

Li Nainai asked, "Is this usable?"

"It's been trial‑running on the street for a week," Zhao Jianguo said, "It processes three hundred kilograms daily, with an error rate under three percent."

The news spread, and the Street Technology Expo invited him to exhibit.

At the judging panel, an expert flipped through documents, brow furrowed, "The inventor is you? Xu Da Mao?"

"It's me." Xu Da Mao stood, back straight.

"Do you have a technical title? What about your education?"

"None. But I've done over seven hundred tests, all the records are here."

He handed over a notebook, densely packed with data—time, temperature, error values—nothing omitted.

The expert finished reading, passed it to a colleague. The other flipped a few pages, nodded, "The data is genuine."

The live demonstration began. The robot accurately sorted twenty different waste types, even mud‑stained cans could be identified.

A reporter snapped a photo and asked, "Mr. Xu, what do you think made you create this invention?"

Xu Da Mao looked toward Zhao Jianguo standing in the back row.

"It was my brother Zhao who gave me the chance," he said, "He never asked what I'd done before, only what I want to do in the future."

Applause erupted.

That night Zhao Jianguo sat in his study and opened the system interface.

【Prodigal Son Return Task Completed】

【Reward: Transformation Case Database — containing historical successful conversion pathways and psychological intervention models for marginal individuals】

He clicked open and glanced; inside were several modules: Trust Building Cycle Table, Skill Matching Evaluation Form, Social Reintegration Support Plan.

Useful.

He closed the device, was about to stand, when a knock came from outside the door.

"Brother Zhao." It was Xu Da Mao's voice, "May I come again to hear tomorrow's class?"

"Come." Zhao Jianguo said, "Next week I'll teach Programming Basics."

"Alright."

Footsteps faded away.

Zhao Jianguo walked to the window; the robot in the Courtyard was still charging, its indicator light blinking.

He was just about to pull the curtain when he heard footsteps again outside.

Looking up, Xu Da Mao had returned.

He was carrying a Meal Ticket in his hand.

"I had Sha Zhu stir‑fry a dish for me," he said, "Thinking… you might not have eaten today."

Zhao Jianguo was stunned.

Xu Da Mao handed over the Meal Ticket, said nothing more, and turned to leave.

Zhao Jianguo took it; the box was still hot.

He opened the lid; inside was neatly cut stewed potatoes and meat, the aroma drifting out.

He picked up a piece and put it in his mouth.

The door was suddenly pushed open again.

Sha Zhu stuck his head in, staring at the Meal Ticket in his hand.

"I fried that," he said.

Zhao Jianguo nodded, "I know."

"I didn't make it for him," Sha Zhu glared, "I made it for the people working in the Courtyard!"