In “At the Vacancy Sign,” Charles Simic expresses many negative emotions; his structural choices reflect that sadness. Let's look at how this works.
First, notice the short, choppy lines of the poem. They provide a staccato rhythm that taps out a near despair. Also, look at how fragmented each stanza is. There is not a single complete sentence in this poem. Every phrase is an incomplete fragment, often left hanging without a verb, a subject, or both. These choices leave us staggering from phrase to phrase, image to image, wondering where the poem is going.
Let's look at an example from the fourth stanza:
Empty sleeves dangling
On a chair across the room.
This bleak image is split into short phrases, which contributes to its bleakness. The rhythm is choppy, and the sentence is incomplete. Like the empty suit, it is missing something. The suit is missing the human being, while the lines are missing the spark of hope; their structure reflects their content.
Now read through the poem again, and pick out a couple more examples of places where the poem's structure mirrors its imagery or message. Indeed, you will find that the poet does an excellent job of weaving sadness and negativity directly into his poem.