'That will be John' I understand the sense of this phrase and the like but in them the subject is 'that'. Are sentences in which 'will be' or 'will have' is used with another subject (like 'he will be ...', 'he will have.. ' or 'he will NOT be...', 'he will NOT have.. '), and which do not relate only to the future, used in English?
Thank you in advance.
That's the 'will' of certainty, and can be used with any subject.
That will be John. He will be hungry. Mary will be with him.