Final answer:
The group of words 'Built to honor all the gods' is a phrase. It functions as an adjective, providing additional information about the Pantheon.
Step-by-step explanation:
The group of words in bold, 'Built to honor all the gods', is a phrase. A phrase is a group of words that functions as a single part of speech but does not have a subject-verb relationship. In this case, the phrase is functioning as an adjective, modifying the noun 'Pantheon'. It provides additional information about the purpose or nature of the Pantheon.
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