"I forgot. Uh, thank you, my little sister."

Mengmeng turned around and thanked Felina.

"I am not your little sister." Felina tilted her head to the side.

"I've done the math. You are a little younger than me," Mengmeng said. Then, she shifted her focus to driving again.

"What did I do wrong? Did I switch to the wrong gear?"

After studying the gears for a while, Mengmeng finally understood the correct way. On her second ...