Interrogative is a term used in grammar to refer to features that form questions. Thus, an interrogative sentence is a sentence whose grammatical form indicates that it is a question. Such sentences are sometimes said to exhibit an interrogative mood—thus treating interrogative as one of the grammatical moods, specifically a type of epistemic mood. This applies particularly to languages that use different inflected verb forms to make questions.
Certain languages mark interrogative sentences by using a particular inflection of the verb (this may be described as an interrogative mood of the verb). Languages with some degree of this feature include Irish, Scottish Gaelic, Welsh, Greenlandic, Nenets, Central Alaskan Yup'ik, Turkish, Korean and Venetian.
In most varieties of Venetian, interrogative verb endings have developed out of what was originally a subject pronoun, placed after the verb in questions by way of inversion (see following section). For example, Old Venetian magnè-vu? ("do you eat?", formed by inversion from vu magnè "you eat") has developed into the modern magneto? or magnèu?. This form can now also be used with overt subjects: Voaltri magnèo co mi? ("do you eat with me?", literally "you eat-you with me?").
In Turkish, the verb takes the interrogative particle mı (also mi, mu, mü according to the last vowel of the word – see vowel harmony), with other personal or verbal suffixes following after that particle:
Geliyorum. ("I am coming.") → Geliyor muyum? ("Am I coming?")
Geliyordum. ("I was coming.") → Geliyor muydum? ("Was I coming?")
Geldim. ("I came.") → Geldim mi? ("Did I come?")
Evlisin. ("You are married.") → Evli misin? ("Are you married?")












