The correct verb form to complete Fabián's letter is 'suben' as it agrees with the plural subject 'Patrícia y Rosa'. This indicates that both girls are climbing the mountain. Therefore, the correct sentence reads: 'Patrícia y Rosa suben una montaña.' ;
The correct verb form to complete the sentence is 'suben', which means 'they climb', matching the plural subject 'Patrícia y Rosa'. Therefore, the complete sentence is 'Patrícia y Rosa suben una montaña.'
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