Question

explain - beneath all uniforms a single body breathes

Answer 1

Hello friend ,
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It means that inside the different and colourful dresses everyone have same body (every part of body is similar .Example -eyes , nose )
No one in this world is different , no one is strange .

It is from poem-no men are foreign.
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I hope it help you

Answer 2

Here the poet says that underneath of uniforms all are same only the dresses vary. All humans breathe the same air whether it be a enemy or friend