We use Stanford named entity recognizer (NER) (Finkel et al., 2005) to identify CoNLL style NEs 7 as possible answer strings in a candidate sentence for a given type of question.
if the question is ABBR type, we tag CoNLL LOC, ORG and MISC entities as candidate answers; If the question is HUMAN type, we tag CoNLL PER and ORG entities; And if the question is LOC type, we tag CoNLL LOC and MISC entities.