Final answer:
The correct form of the verb perder is pierde.
Step-by-step explanation:
The correct form of the verb perder to fill in the blank in the sentence is OC. pierde. The sentence should read: Mis padres siempre pierden las llaves. In this sentence, the subject is 'mis padres' which means 'my parents' in English. The verb 'pierden' is the correct form to match with the third-person plural subject.
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