  Emerging research in Neural Question Generation (NQG) has started to
integrate a larger variety of inputs, and generating questions requiring higher
levels of cognition. These trends point to NQG as a bellwether for NLP, about
how human intelligence embodies the skills of curiosity and integration.
  We present a comprehensive survey of neural question generation, examining
the corpora, methodologies, and evaluation methods. From this, we elaborate on
what we see as emerging on NQG's trend: in terms of the learning paradigms,
input modalities, and cognitive levels considered by NQG. We end by pointing
out the potential directions ahead.
