Repitition

What is repitition: In poetry where you say the same thing multiple times usually in the same space of different stanzas.
Example: Roses are red
                  Violets are blue
                  This is the place
                 Where i love you

               Wether the sky be grey
               or sky be blue
              This is the place
               where i love you.

Why do we need this? It helps add depth to our poetry.
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