Student or Learner
---Have you finished the book?
---No, I've read up to ________ the children discover the secret cave.
What word would you use for the gap? Thanks!
A better title would have been Have you finished the book?
'Thread titles should include all or part of the word/phrase being discussed.'
I agree that 'where' is possible. I think it's the most natural choice, but feel that 'when' is also acceptable.