Question: Hello Albert,
This is something I have been pondering on for a long time and now question, how long is a phrase, could it be one page or half a page?
If one learns phrase by phrase using all their concentration and accuracy, then surely by the time they get to the end of the piece of music, they should be able to play it thoroughly by memory, is this true?
Many thanks.Brian (Colombia)
Albert's reply: Brian, thanks for an excellent question. Phrases have to do with the interaction of harmony with melody, but you can often recognize them from the melody alone, since the melody usually implies harmony.
Let's use "Twinkle, Twinkle, Little Star" as an example. (It's actually an old French nursery rhyme called "Ah, vous dirai-je, maman.") Here is Mozart's arrangement, with a single-voice accompaniment:
After the first four measures ("Twinkle, twinkle, little star") we're not satisfied (even though the harmony has returned to the tonic: I-IV-I for more advanced students). The reason is that the melody is on the fifth scale degree, G. We need for it to return to scale degree 1 (C in this case), or at least to 3—and for this to coincide with a tonic harmony (a C major chord). (The other general option is for the phrase to end on the dominant, or V—in this case a G major triad. This would end the phrase, but not the period. We'll get to this later, as this is more advanced.)
The first phrase continues all the way to the end of the line ("how I wonder what you are"), and totals eight measures. Here, both the melody and harmony reach C, which is our key-note or tonic, since we're in the key of C major.
The second phrase ("Up above the world so high, like a diamond in the sky") is likewise eight measures, and it can be split into 4 + 4 with both halves virtually equal. This second phrase end on the dominant (a G major triad), so now we expect the return of the tonic... which comes with the repeat of the first phrase.
Phrasing is not always so clear in music, since composers often do things such as elide one phrase into the next. Songs are usually very good for learning phrasing, as the lyrics usually demarcate musical phrases for us.
As for your second question regarding memorizing music, I wouldn't put it quite so simply, since the memorization process is quite complex and involves multiple faculties. Each person tends to learn somewhat differently from the next, some automatically favoring visual memory over aural memory, and most learning piano by kinesthetic memory (muscle memory). I'll treat this complex topic separately!
For now, just remember that musical phrases are generally smaller sections of music that make sense to the ear, the way phrases in speech make sense.