The poem opens with a tercet, a three-line stanza, that serves as the speaker's introduction. The speaker (who is never named nor gendered in the poem) seems to be responding to some unseen party who has deemed the speaker "half-caste"; this other party—addressed in the second person throughout the rest of the poem—can also be understood as a stand in for society itself.
The term "half-caste" is inextricable from ideas of racial hierarchy. The word has roots in the Latin term castus, meaning chaste or pure. The idea of being "half-caste" thus suggests a muddying of racial purity, and also brings to mind derogatory terms like "half-breed," "mulatto," or "quadroon"—deeply offensive labels that attempt to categorize people based on their amount of black ancestry. The word "caste" itself is perhaps most often associated with the social stratification of India, where traditionally people have been born into strictly segregated castes that reflect cultural ideas of purity.
The speaker responds to the idea of being "half-caste" by employing humorous imagery that depicts a literal "half" person, with only one leg to stand on. The poem thus immediately sets the stage for the theme it will explore—the absurd manner in which racism boils people down to little more than labels of black or white, leaving no room for a more nuanced human identity.
The first three lines of the poem have no punctuation, which allows for a variety of interpretations when it comes to the speaker's tone. The "Excuse me" could be a statement of genuine confusion or mishearing, but, as the poem goes on, it becomes clear that the speaker is only pretending to be ignorant of the implications of being called "half-caste." The initial stanza, viewed in this light, feels defiant and biting—a sarcastic response to a racist label, akin to saying something like, "Seriously?"
These opening lines do not fall into any established order in terms of rhyme, meter, or formal verse. They consist of a brief declarative sentence, split over three lines. The lack of consistent rhyme, meter, or form will be carried throughout the entirety of the poem. In the lines to follow, a Caribbean Creole dialect is employed, however, lines 1-3 are written in so-called "proper" English.
This introductory tercet is complemented by a concluding tercet. The only two stanzas of equal lengths, stanzas 1 and 4, thus serve to book-end the exploration of half-caste that occurs in stanzas 2 and 3. Stanzas 2 and 3 are 27 and 19 lines each, respectively. This unevenness allows the mirroring of the three-lined introductory and concluding stanzas to stand out.