Final answer:
The correct conjugation of 'ser' in Spanish is 'es'.
Step-by-step explanation:
The correct conjugation form of 'ser' to fill in the blank is 'es'. So the sentence should be: 'El carro es grande.'
'Ser' is used to describe permanent or inherent characteristics of something or someone. In this case, 'grande' is describing a characteristic of the car, which does not change.
Other examples of conjugations of 'ser' are: 'yo soy' (I am), 'tú eres' (you are), 'él/ella es' (he/she is), 'nosotros/as somos' (we are), 'vosotros/as sois' (you all are), 'ellos/as son' (they are), etc.
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