Often poems visually “say” as much with their silence as they do with the words that make them up. Poems can be punctuated to facilitate or to detract from their metrical pattern, for example, and the commas and periods and parentheses can create effects not limited to the rhythm (Percy Shelley’s “Ode to the West Wind,” for example, should make you hyperventilate if read properly, since so much of it is enjambed—this is the term for a poetic sentence that continues over two or more lines without end-stopped punctuation. When you read the poem aloud, you continue as if there were no line break; but even though the convention says not to pause, there’s the inevitable time it takes for your eyes to run to the beginning of the next line, and poets often play with that instant to manipulate and influence the meaning of the poem. For example, in Wallace Stevens’s poem Notes Toward a Supreme Fiction, one section considers the very-impressive powers of an unnamed President:
The President ordains the bee to be
Immortal. The President ordains. But does
The body lift its heavy wing, take up,
Again, an inexhaustible being, rise
Over the loftiest antagonist
To drone the green phrases of its juvenal?
The answer to the question is no, since the bee exists with or without the President’s command, and indeed human beings have very little power over bees. The enjambment of the lines reinforces this conclusion – first of all the “bee” already includes its own license to “be,” the pun within its name. But the enjambment of “be / Immortal” (use a forward slash to indicate line breaks when you quote poetry within body paragraphs), for an instant leaves us with the ludicrously unnecessary “bee to be” before introducing us to the President’s impossible command. The next lines clearly question the President’s powers, but the observant reader already got the message thanks to the enjambment. When enjambment disrupts or prolongs the syntax of a line, we call that “hard” enjambment (such as in the Stevens poem above); when it breaks up a sentence into one or more generally coherent clauses, we call that “soft” enjambment. The process of dividing content into different lines on a page is lineation, and it always has consequences for a poem, especially if the poem is written in free-verse. In that case, the lineation is the only thing separating the poem from the look of prose.
Because of all of these visual and auditory effects, you want to try to reproduce as best you can the original structure of the poem in your own writing. If it’s a four-or-more-line passage you wish to cite, make it into a block quotation (as I’ve done above), and make sure you faithfully reproduce all the punctuation and capitalize the first words of every line if that’s how it is in the poem. If it’s shorter than four lines, work the quotation into your sentence, and use a forward slash to indicate where the poem splits the line(s) up.