Final answer:
The correct verb form to complete the sentence is 'podría'.
Step-by-step explanation:
The correct verb form to complete the sentence is podría.
The sentence is in the formal form, as indicated by the use of 'usted' in the first question. Therefore, we need to use the third-person singular form of the verb 'poder,' which is 'podría'.
The full sentence in Spanish would be:
Juan: Necesito el recibo. ¿Usted me podría dar uno?
Learn more about Verb forms in Spanish