Final answer:
The sentence "Juan está corriendo en la calle" is grammatically correct.
Step-by-step explanation:
The sentence "Juan está corriendo en la calle" is grammatically correct. In this sentence, 'Juan' is the subject, 'está corriendo' is the verb phrase that means 'is running', and 'en la calle' is the prepositional phrase that means 'in the street'. This sentence follows the standard Spanish sentence structure of subject-verb-object.
Learn more about Spanish sentence structure