Final answer:
The correct Spanish conjugation of the verb [to write] in the sentence 'Mis amigos y yo [write] cartas' is 'escribimos' which means 'we write'.
Step-by-step explanation:
The correct Spanish conjugation of the verb [to write] in the sentence 'Mis amigos y yo [write] cartas' is 'escribimos'. The subject 'Mis amigos y yo' refers to 'we', so the correct verb form is 'escribimos' which means 'we write'.
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