its a universal language. I believe the use of repetition does three things in this poem: it shows that people from all walks of life sing their own song—it is a part of them and, The word I notice repeated most often is "singing," which ties in with Whitman's title, "I Hear America Singing."
Making inferences means to draw reasonable conclusions. This process involves analyzing the evidence of the text because this is the support of the inference and using background knowledge or information you already know.