The future perfect tense is formed by using the helping (auxiliary) verb of “will have” followed by the past participle form of the verb (ends with “ed” or “en” for regular verbs). This tense shows something happening in the future before something else also happens in the future. Essentially, it is the past in the future, with both actions occurring in the future. Consider the following examples:
Example 1: Dan will have studied for six hours by the time he is finished (Dan’s six hours of study time takes place before he is done studying, but both actions occur in the future).
Example 2: The dancers will have to exercise regularly to maintain their physique (exercising regularly takes place before the dancers can maintain their physique, but both actions occur in the future).