What are question and answer phrases in piano music?

Answer 1

A question phrase, usually four or eight bars, (More technical: ends on a second, forth, fifth, or seventh scale tone, usually ending on a V or V7 chord), and while it often pauses like the end of a phrase, it doesn't quite feel complete. You feel like it needs a little bit more before you feel like it's done. This is the "question phrase," because it kind of feels like a question: a complete sentence, but it needs an answer.

The answer phrase is usually the same number of bars as the question phrase, and it feels like it completes that feeling you felt with the question phrase.

Here's an example. Think of the tune "Mary had a little lamb."

The question phrase is this:

Mary had a little lamb, little lamb, little lamb...

Notice how it feels like a complete phrase, is technically a complete sentence, but we feel like it isn't over yet. (more technical: the last note isn't the first scale degree, or "do" in solfege, the last chord is a V chord.)

The answer phrase is this:

Mary had a little lamb, it's fleece as white as snow.

Notice how this feels complete. It answers the question phrase, and now feels complete. (more technical: the last note IS the first scale degree, or "do" in solfege, the last chord is a I chord.)

Still a little confused? Here's another example hopefully even simpler. Think of the tune "Ba ba black sheep."

The question phrase is this:

Ba ba black sheep, have you any fur?

Notice how this one is actually a question! Not always in music will it be this clear, because you won't always have lyrics and the lyrics won't always be in question form, as we saw with the first example. Here, the melody reflects the literal question in the lyrics and feels incomplete and needs a musical answer.

The answer phrase is this:

Yes sir, yes sir, three days full.

Notice it's an actual answer! Again, you won't always see such a literal example. But notice how it literally and musically answers the first question phrase. Even though the song keeps going, this part feels complete.