Final answer:
The sentence "Tú soy vieja." is incorrect because the verb "soy" should be used with the pronoun "yo" and not "tú". The correct sentence would be "Tú eres vieja."
Step-by-step explanation:
The sentence "Tú soy vieja." is incorrect. The verb "soy" means "I am" and should be used with the pronoun "yo" not "tú". The correct sentence would be "Tú eres vieja." where"eres" is the second person singular form of the verb "ser" which means "to be".
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