Max sat at his desk, staring at Exercise 142 in his . The task was a nightmare: he had to identify every case of the nouns and explain the spelling of unstressed vowels. The clock on the wall ticked loudly. It was already 8:00 PM, and his favorite video game was calling his name.

The screen flickered. A website with a bright yellow background appeared. But instead of just a list of answers, a small, pixelated character with a giant red pen appeared on the screen. It was the "Grammar Ghost." "Looking for a shortcut, Max?" the Ghost squeaked. Max jumped. "I'm just... verifying!"

The Ghost offered Max a deal. "I won't give you the answer for Exercise 142. But, if you look at the for Exercise 140, I’ll show you the trick for finding the root of the word. If you learn the trick, you can do Exercise 142 yourself in three minutes."

Five minutes later, Max had finished the homework on his own. The pixelated Ghost gave him a thumbs-up and vanished.

"Verifying is fine," the Ghost said, pointing its pen at the screen. "But if you just copy, the knowledge stays on the screen and never enters your head. Then, when the test comes tomorrow, your pen will feel like it weighs a hundred pounds."

The next day, Mrs. Ivanova called Max to the board. "Max, explain why 'лесной' is spelled with an 'е'."