in the first stanza dunbar uses the line "i know what the caged bird feels" and repeats the line again in line #7. This is an example of what poetic device?

This is an example of repetition.

Explanation:

As a poetic device, repetition consists of repeating a certain word, phrase, or sentence, usually with the purpose of emphasizing or clarifying an idea.

In Dunbar's poem "Sympathy", the sentence "I know what the caged bird feels" is repeated in the first stanza. The speaker's purpose is to emphasize the feeling of being trapped, like a bird in a cage. Of course, that idea is developed in the other lines as well, but the fact that this one sentence is used twice in the same stanza, in its first and last lines, helps create this sense of suffocation, or imprisonment.

a lot

explanation: