Do this tanka poem have clear structure or rhyme?

Tanka poems always have a structure, but not the rhyme.

They follow the pattern of syllables which goes like this:

line - 5 syllables line - 7 syllables line - 5 syllables line - 7 syllables line - 7 syllables

It is very similar to haiku, but a bit longer and more elaborate. It also uses metaphors and allusions, and no punctuation.

Even when translated on English it doesn't seem to us tanka has a structured form, we must know that on the original Japanese version it is structured with the model showed above.