The future perfect tense is used to describe an action that will have been completed at some point in the future.

For example:

1. John will have cooked dinner.
2. They will have painted the fence.

Structure of future perfect tense sentence:

Subject + will have + past participle

Examples:

1. By the time they arrive, we will have finished our work.

(Note: "By the time they arrive" identifies the point in the future)

2. I will have read every magazine in the waiting room before I see the doctor today.

(Note: The clause "before I see the dentist" identifies the point in the future.

Negative sentence formation:

1. By the time they arrive, we will not have finished our work.
2. I will not have read every magazine in the waiting room before I see the doctor.

Note: "will not" is sometimes written as the contraction "won't."

Interrogative sentence formation:

1. By the time they arrive, will we have finished our work?
2. Will I have read every magazine in the waiting room before I see the doctor?

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