If a poem has six feet how many syllables does it have

twelve syllables

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If a poem has six feet, it has twelve syllables.

Explanation:

In poetry, we have different kinds of feet. Since your question does not mention any specific type, let's assume it refers to the most common one, the iambic foot. A iambic foot is constituted of an unstressed syllable followed by a stressed one. If you have an iambic tetrameter (tetra means four), that means your have 4 feet, or four pairs of syllables. If it is an iambic pentameter, you will have 5 feet. According to your question, the poem has 6 feet. Therefore, it has 6 pairs of syllables or, in other words, twelve syllables. An example of a line with 6 feet would be (the stressed syllables are in bold):

The things / which I / have seen / I now / can see / no more. - - William Wordsworth