The voice returned, now soft. "Excellent. You have used context, idiom, and lateral thinking. Your English level is: Operational Proficiency. Session complete."

"Use the Work module," she'd said. "The software can hear the mistakes."

"Worked... wrought?" he whispered. No. Then it hit him. The past tense of to work in an archaic sense: WROUGHT . Wrought iron. Wrought metal. But a tool for repairing a PDF?

A minute later, her reply arrived. It contained only three words: "Well wrought, Leo."

Leo frowned. He hadn't seen this in the original PDF.

But as he reached page 47, the voice changed. It deepened, grew metallic. "Final exercise. Real-world application."

Leo muttered, "B. Plow through." The software beeped. Correct.