Preliminary
Part of speech: adjective
Definition: in preparation for the main matter; initial, introductory, preparatory
Part of speech: noun
Definition: A preparation for a main matter; an introduction Any of a series of sports events that determine the finalists A relatively minor contest that precedes a major one, especially in boxing
Example sentence: It is evident that one cannot say anything demonstrable about the problem before having resolved these preliminary questions, and yet we hardly possess the necessary information to solve some of them.
Explorative
Part of speech: adjective
Definition: exploratory