Lesson 511: Explore: The book exchange

Keep a steady pace. The speed target is a guide; 85% accuracy completes a lesson.

The building had found a quiet way to share something valuable. A little shelf stood near the entrance to the apartment building. Residents could leave a book and take another one home. Some pages carried notes from readers who had come before. A mystery novel disappeared on Monday and returned on Friday. "Shall we try again?" someone asked. The simplest part of the plan proved the most useful.