What does the future perfect tense describe?

The future perfect tense describes an action that will occur before some other future action. It is formed using "will have" followed by the past participle of the main verb. This construction indicates that there is a specific point in the future by which the action is anticipated to be completed. For example, in a sentence like "By next year, I will have graduated," the graduation event is expected to be completed before the point in time referenced (next year). This tense is used to provide clarity in timelines, showing a clear relationship between two actions in the future, where one is completed prior to the other.

The other options do not accurately represent the future perfect tense. The first option refers to simultaneous actions, which aligns with the simple present or present continuous tense rather than the future perfect. The choice describing an action that has already begun relates more to present perfect or past progressive tenses. Lastly, the indefinite action in the past fits the simple past or past perfect tense but does not reflect the predictive nature of the future perfect.