Final answer:
The given French sentence 'Lui et moi, nous parlons français' is grammatically correct. The pronouns 'lui' and 'moi' function as the subject.
Step-by-step explanation:
The given French sentence 'Lui et moi, nous parlons français' is grammatically correct. The pronouns 'lui' (him) and 'moi' (me) function as the subject of the sentence, indicating that the speaker and another person are speaking French.
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