Future perfect continuous tense
Usage
Duration of an action that will be ongoing until a future point in time: The future perfect continuous tense is used to describe an ongoing action that will continue until a specific point in the future.
By this time next week, I will have been working on this project for three months.
Emphasis on the duration of the action: The future perfect continuous tense emphasizes the duration of an action that is expected to continue until a future point in time.
By the end of this year, I will have been living in this city for ten years.
Connection between two future actions or events: The future perfect continuous tense is often used to describe an action or situation that will be ongoing until another future action or event happens.
I will have been traveling for three weeks by the time I return home.
Form
The future perfect continuous tense is formed using the future perfect of the auxiliary verb will followed by have been and the present participle (-ing form) of the main verb.
I will have been studying for two hours by the time my friend arrives.
Signal words
The future perfect continuous tense is typically used with action verbs that describe ongoing actions, such as study, work, run, or swim.
Negative and question forms
To form negative sentences in the future perfect continuous tense, the word not is placed between will and have been
I will not have been studying for two hours by the time my friend arrives.
To form questions in the future perfect continuous tense, the auxiliary verb will is moved before the subject
Will you have been studying for two hours by the time your friend arrives?