PAST FUTURE PERFECT TENSE

THE  FUTURE PERFECT TENSE

 indicates that an action will have been completed (finished or "perfected") at some point in the future. This tense is formed with "will" plus "have" plus the past participle of the verb (which can be either regular or irregular in form): "I will have spent all my money by this time next year. I will have run successfully in three marathons if I can finish this one."

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