This paper proposes a set of hypotheses on the nature of interrogration as a possible language universal. Examples and phrase structure rules and diagrams are given. Examining Tamazight and English, genetically unrelated languages with almost no contact, the author distinguishes two types of interrogation: (1) general, querying acceptability to the hearer of the speaker's proposition, as in English yes-no questions, and (2) local, requiring completion of the speaker's proposition, as in English wh-questions. Interrogative sentences share with possible non-interrogative constructions underlying modes characterized as: declarative, positive, interrogative, affirmative, ablative, focussed. (Negative can apply to these and others, but is not relevant to the discussion.) Local questions correspond only to focussed constructions and are closely related to relative clauses. General questions may correspond to either focussed or unfocussed constructions and are closely related to conditional clauses. (MK)