<Tr> <Td> A3 </Td> <Td> When I'm alone with only dreams of you that won't come true...What'll I do? </Td> </Tr> <P> Some Tin Pan Alley songs composed as numbers for musicals precede the main tune with what was called a "sectional verse" or "introductory verse" in the terminology of the early 20th century . This introductory section is usually sixteen bars long and establishes the background and mood of the number, and is musically undistinguished in order to highlight the attractions of the main tune . The sectional verse is often omitted from modern performances . It is not assigned a letter in the "AABA" naming scheme . </P> <P> The introductory verse from "What'll I Do" by Irving Berlin is as follows: </P> <P> Gone is the romance that was so divine,' tis broken and cannot be mended You must go your way, and I must go mine, but now that our love dreams have ended...</P>

A composition in a-a-b-a form has how many melodies