Querying the graph

I have constructed a graph from csv file having triples (node->relationship->node) in neo4j. How can I use this graph built to extract answers for questions asked in the form of English statements?

The same way. You can represent your english statements as Subject-NOUN->Verb
Of course stemming etc.

Our partner GraphAware.com has a lot of articles about NLP and answering questions from your data.
e.g. /cc @Christophe_Willemsen