Technical Term Needed

Solution 1:

There's no single term that covers these because you're mixing up several dimensions.

Interrogative is, if anything, a mood, or mode; anyway, a part of modality. All interrogative means is "(this is a) Question". There are a lot of different kinds of questions, aren't there?

Questions are opposed to Assertions (or Statements), sentences which can be either true or false (questions can't be true or false), and Imperatives, which simply means "(this is an) Order", and only uses infinitive forms with 2nd-person subjects. Imperatives can't be true or false, either; Get out of here! is no more true and no more false than What time is it?.

Affirmative and Negative, on the other hand, while they are often opposed in binary situations, have quite different roles. They can both apply to statements, and negative can apply to questions as well, which is where the confusion lies.

Affirmative statements are those that aren't negative. That's about all you can say about them, as a class. It always seems ironic to me that affirmative has a negative description. It's not a grammatical term in general, unless one needs a term to contrast with negative.

Negation, on the other hand, is a BIG topic in logic and grammar; it's not simple at all. And it's common to have negative questions, as well as affirmative ones:

• Have you eaten breakfast?
• Haven't you eaten breakfast?

Since the negative in a question can't be denying anything, it's used to signal the speaker's presupposition (in this case, the suspicion that the addressee has not in fact eaten breakfast, although the speaker had expected the addressee to).

In general, when dealing with grammatical and semantic notions, one needs more than two dimensions, and some interesting math. Especially if those notions involve negation, modality, or quantification.