This paper is the first step to an exact analysis of one of the most important of leaching methods — that of dialogue. The essence of a dialogue is a sort of harmony between questions and answers, which analysed from the view of logic and semantics. The paper contains a classification of Questions and answers as well as a classification of their mutual relationship (general and direct questions, special and alternative questions, adequate and inadequate answers, truthful and untruthful answers, etc.). Logically adequate and simultaneously truthful answers are called fitting answers. The paper ought to contribute to a partial formalization of the language of questions and answers, and it ought to be a basis and a starting point for the next experimentally pedagogical stage of the questions and answers analysis. The conclusion of the paper contains some remarks about the characteristic and specific features in using the questions and-answers method in the teaching process.