Final answer:
The best translation of the sentence 'You (tú) wouldn't do it' is 'No lo harías.'
Step-by-step explanation:
The best translation of the sentence 'You (tú) wouldn't do it' is 'No lo harías.' In this case, 'lo' is used as a direct object pronoun and 'harías' is the second person singular form of the verb 'hacer' (to do). 'Harías' matches the subject 'you' in the sentence.
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