Final answer:
The sentence "Alicia y Paula están caminando" is grammatically correct.
Step-by-step explanation:
The sentence "Alicia y Paula están caminando" is grammatically correct. In Spanish, when two or more subjects are connected by the conjunction "y" (which means "and"), the verb should be conjugated in the third person plural. In this case, the subject is "Alicia y Paula" (Alicia and Paula) and the verb "están" (are) agrees with them.
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