Final answer:
The correct form of the verb is arrivions.
Step-by-step explanation:
The correct form of the verb to complete the sentence is arrivions.
The sentence is in the subjunctive mood, which is used in situations of doubt, uncertainty, or desire.
In this case, the verb craint triggers the subjunctive, and the subject nous requires the conjugation of the verb arriver in the subjunctive form, which is arrivions.
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