Is the group of words in bold a phrase or a clause?

Built to honor all the gods, the Pantheon is a monument that is an exceptional example of ancient Roman architecture.

1 answer

In the sentence you provided, the bolded group of words "Built to honor all the gods" is a phrase. It does not contain a subject and a verb that express a complete thought, which is characteristic of a clause. Instead, it functions as a participial phrase that provides additional information about "the Pantheon."