Final answer:
The correct verb form to complete the sentence is 'respeten'
Step-by-step explanation:
The correct verb form to complete the sentence is respeten.
In this case, the subject 'los extranjeros' requires the verb form 'respeten' as it is in the third person plural form.
For example, the complete sentence would be 'Es una pena que los extranjeros no respeten las tradiciones locales.'
Learn more about Verb forms in Spanish