Specify new distractor types by constraints they require or prohibit

[JackMostow]

DQGen can generate distractors of three different types: ungrammatical, nonsensical and plausible. To make DQGen more extensible, we want to use some constraints rather than distractors types to generate distractors. For example, an ungrammatical distractor should have a wrong part of speech(POS), while a nonsensical distractor should have a correct POS, but should never occur in Google n-grams. Also, a plausible distractor should occur in Google n-grams but not consistent with the context in the question. So, it is very easy to generate a new type of distractor by using a combination of some constraints, and this will make DQGen more extensible and generalizable.