Final answer:
The appropriate verb in the conditional tense to fill in the blank is "deberían" meaning "should"
Step-by-step explanation:
The appropriate verb in the conditional tense to fill in the blank in the sentence "Ustedes ________ ir a Teotihuacán, porque está cerca de la Ciudad de México" is deberían. The verb deberían means "should" in English and is the correct form to use for the subject "ustedes" which is the second person plural. This form indicates that the subject "ustedes" should go to Teotihuacán because it is near Mexico City.
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