1. How does chapter 33 end? What interpretations can you make?

The boys return to the Glade and go to the Map room to record their day's work. After that, a quick dinner and Thomas returns to his favorite sleeping spot in the Deadheads. Being a Runner has already lost its glamour, after only a single day.

As he begins to drift off to sleep, Teresa's voice reverberates inside his head. "Tom", she says, "I just triggered the Ending."

Because they always have a safe place to return to, they haven't had a reason to be desperate to escape. After two years they have essentially made no progress.