Future perfect simple ( I will have worked eight hours )
https://dictionary.cambridge.org/grammar/british-grammar/future-perfect-simple-i-will-have-worked-eight-hours
WebFuture perfect simple: use. Events finished by a certain time in the future. We use the future perfect form when we look back to the past from a point in the future. We usually use a time phrase, for example by tomorrow, for three years: Do you think she’ll have seen the doctor by four o’clock?
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