How do I identify events from a text document?

How do I identify events from a text document?

Events in the noun-sense would be Named-entity recognition. Events in the verb-sense would be triple extraction (aka tuple extraction).

TPE Based Tuple Extraction Method for Question and Answering System(2014):

In order to develop effective question and answering (Q&A) system, it is necessary to analyze syntactic structures of sentence and extract a set of semantically important words (tuple) from them. In this paper, we propose Tree Pattern Expression (TPE) based tuple extraction method for high-performance Q&A system. To extract tuples from target sentences more accurately than conventional Q&A systems, TPE and its fast pattern matching algorithm are used. A tuple consists of subject, predicate, object, preposition and its object, which may contain a correct answer part for a given question. In experiments, our TPE based method performs much better than traditional ones for Q&A system, as we expected, because our method elicits key structures of complicated sentences elaborately and thus extracts their associated tuples more accurately.