Q) Next month, I _______ John for 20 years
(A) know
(B) will have known
(C) am knowing
(D) will have been knowing
Question bank says (D) is correct. Surely, (B) is the correct one, right?
Edit:
I request answers/comments that reflect common practices of American and British English.
D is certainly not idiomatic in British English, nor I think American. B is the only natural choice.
It is possible that D is idiomatic in Bangla Deshi English: I don't know.
Most verbs I can think of where “I will have been” doing something in the future perfect progressive are for actions that could be stopped and started over, resetting the clock, whether or not that has in fact happened.
So, for example, if I lived in Kalamazoo for ten years, then moved away, then moved back eleven months ago, I will have been living in Kalamazoo for one year next month, but I will have lived in Kalamazoo for eleven years. (This is not, however, an ironclad rule: people sometimes say something like, “I will have been living in Kalamazoo for eleven years, with some interruptions.”) If I moved to Kalamazoo for the first time eleven months ago, however, “I will have been living in Kalamazoo for a year,” and “I will have lived in Kalamazoo for a year,” would be synonyms.
So, examples of where the construction in D would be idiomatic (in American English) include “I will have been living with John for twenty years,” “I will have been fighting John for twenty years,” “I will have been avoiding John for twenty years,” “I will have been working with John for twenty years,” “I will have been hiding from John for twenty years,” and “I will have been dating John for twenty years; why do you say he’s afraid of commitment?”
Know doesn’t work that way; once you meet someone, you always “know” that person. (There is an expression, “I don’t even know him anymore,” but it isn’t taken literally, and if you asked that person, “Do you know John?” the answer would still be “Yes.”) An even simpler reason, though, might be that we don’t normally “*be knowing” someone, in any tense. Emotional states (such as hating and loving) are another set of examples that are not normally used as progressive verbs. (Again, in American English.)
The correct phrasing is B. In US English, the verb "know" is not used in a continuous or ongoing (or active) sense in regard to people. We do not speak of "knowing" a person. ("I have been knowing him", or "It has been 20 years of knowing him" are not used.) You know someone or you don't. You have known her for a long time or a short time. You can say you knew him for many years. You can say you would like to know someone.
This is in contrast with the verb "live."
I have been living in Florida for more than 30 years, and I have known some people for that long."
"Know" in the continuous ("knowing") sense is used only in sentences that refer to use of knowledge: "Knowing how to prepare a meal is important for young adults, who otherwise have to spend a lot of money on dining out."
The more common use of 'to know' would mean that John is a person with whom I have been acquainted these past 20 years. In this case, (B), I will have known him, since the action of having come to know him was both begun and completed in the past.
However, there is a more idiomatic use of know, 'to know in the biblical sense', meaning to have had sexual relations with. If John and I are in an ongoing sexual relationship, then that should be expressed in a progressive tense: I first knew John 20 years ago, we have been knowing each other ever since, and next month I will have been knowing him for 20 years, thus (D). It would be the same tense as the more vulgar, 'Next month I will have been f***ing him for 20 years'.
Now, I hardly think this is what the university exam meant to imply - rather, it is a case of their incorrect grammar being coincidentally correct for a different meaning they did not intend.
