Which verb form correctly completes the sentence?
Soon after he turned in his term paper, Bryan _______ he had left out the bibliography.
a. knew
b. known
c. know
d. had knew
A. knew, because if you think about how they all sound, B and C could not work, since they sound kind of weird. D sound like it could work, but only if it was "had known". Therefore the only answer left to pick is "A. knew".
