Example 4. The phrase hierarchy and the “primary division”

Dotted lines show lowest-level phrase divisions; the square bracket shows the chorus’s deepest division, the primary division. Here, inter-onset interval (IOI) suggests that the division in measure 8 is the chorus’s deepest, resulting in a chorus-level 8/4 phrase structure. (“Chi Chi,” chorus 2; Aebersold 1978, 28)