Final answer:
The sentence "Bert es feo" is grammatically correct in Spanish.
Step-by-step explanation:
The sentence "Bert es feo" is grammatically correct. In Spanish, adjectives like "feo" (úgly) agree in gender and number with the noun they modify. Since "Bert" is a male singular noun, the adjective "feo" is also in the masculine singular form. Therefore, the sentence is grammatically correct.
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