“Kubla Khan” uses quite a bit of enjambment throughout, but it does not seem to follow any set pattern or scheme. For instance, the first five lines contain three enjambments, in lines 1, 3, and 4. But the rest of the stanza switches into a heavy string of end-stops. The poems opens at speed, with its lines racing down the page; then it slows, becoming ponderous and heavy.
The switch happens at a key point in the stanza: after line 5, the stanza’s rhyme scheme shifts (and after line 7, the poem switches its meter as well). In this case, internal divisions in the poem's form line up with a switch in the way the poem uses enjambment. And the break between these two sections is reinforced by the end-stop at the end of line 5.
The poem often separates its various formal sections with end-stops. For instance, each stanza finishes with a clear end-stop; there is no enjambment across stanzas. And when the second stanza shifts from iambic pentameter to iambic tetrameter in lines 30-31, the speaker separates the two sections with an end-stop. In some places, then, enjambment and end-stop mark the poem’s separate sections, clarifying the poem’s internal structure.
Alongside these structural uses of enjambment and end-stop, one notes the pleasure with which the poem deploys enjambment: the speaker uses enjambment for surprise, to mislead the reader and then transform their experience of the poem.
For instance, in line 15, the speaker describes the “deep romantic chasm” as “haunted.” Falling at the end of the line, the reader is encouraged to pause briefly over the word “haunted—and imagine the kind of creatures that usually are said to haunt: ghosts and ghouls. But line 16 contradicts these expectations: the “deep romantic chasm” is not “haunted” by a ghost, but by a “woman wailing for her demon-lover.” Instead of being associated with death, the “chasm” is associated with erotic love.
The likely effect of the enjambment is to suggest a blurring together of sex and death, to merge the erotic with mortality. The use of enjambment in this way—to surprise the reader—is relatively unprecedented in English poetry (though one does find it in Milton, for example) and one of the key innovations of the Romantic poets.