Final answer:
The participial phrase you might add to sentence 5 is 'Staying at the inn.'
Step-by-step explanation:
The participial phrase that you might add to sentence 5 is a) Staying at the inn. A participial phrase is a phrase that begins with a verb in its present or past participle form, and it functions as an adjective to modify a noun or pronoun. In this case, 'Staying at the inn' describes the action or state of the noun in the sentence. For example, 'The person staying at the inn entered through the front door.'