The song opens with a syncopated (using offbeat accents) accompaniment figure in 3/4 time. When the vocal part begins, this uses a push rhythm, where the melody is ahead of the beat. It is particularly noticeable on the words ‘be’ and ‘could’. A similar repeated pattern is heard throughout. This is known as an ostinato. The pitches change to fit the harmony.
The accompaniment stays in the background throughout so that the singer can be heard clearly.
When it was written the singers would not have had their voices amplified on stage. The opening accompaniment is played by clarinets (including bass), pizzicato (plucked) strings and drum kit (snare drum and hi-hat cymbal, played with wire brushes).
In the opening, the same bar of accompaniment is repeated several times. This gives time for the actors to move across the stage and is a device often used in musicals.
There are several time signature changes in the song as it moves between 2/4 and 3/4 time. The word-setting is mostly syllabic (one word to a syllable).
There are several examples of triplets (where three notes are played in the time of two).