Final answer:
The sentence "Tú eres eficiente" is correct in Spanish and it means "You are efficient".
Step-by-step explanation:
The sentence "Tú eres eficiente" is correct. In Spanish, the subject pronoun "Tú" means "You". The verb "eres" is the present tense form of the verb "ser" which means "to be". And the adjective "eficiente" means "efficient". So, the sentence "Tú eres eficiente" translates to "You are efficient".
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