Answer:
The implicit meanings of words in the poem.
Explanation;
Theme basically means the message of a story.
More Explanation:
The poetry is a form of literature that uses both rhythmic and aesthetic qualities of language to provoke meanings. Therefore that the theme inside a poem tend to be the implicit understanding that a person gives to the words used in the poem. The theme, also comprehends the lesson about something in particular, like life or human nature, that the poet seeks to spread around his readers.
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