Is the sentence correct?

Under most circumstances, the sentence is incorrect.

If a group of students were discussing a hypothetical class reunion 50 years in the future, one of them might say, "Tom will have been a teacher."

(rolls eyes) Not much help, really, that answer, Noddy!



Except, of course, for those circumstances in which it is correct!

Just like these sentences

Tom is a teacher.
Tom was a teacher.
Tom has been a teacher.
Tom will be a teacher.
Tom might be a teacher.
Tom might have been a teacher.
Tom could have been a teacher.
Tom should have been a teacher.
Tom could be a teacher.

There is absolutely nothing wrong with the sentence.

"unusual" does not equal "wrong". "I don't use this phrase very much" doesn't mean "wrong" either.

Tom graduated from teacher training college in July. He started his first school job in September. When I meet him at Christmas, he will have been a teacher for three whole months.

(rolls eyes) not much help that answer, contrex.

You'll notice what you answered is not quite what Yoong asked. He asked if that sentence was correct. Not whether "By Christmas Tom will have been a teacher for three months" was correct. Noddy's answer comes closer to the gist of the question. Your sentence really needs the additional clauses to make any easily comprehensible sense, unlike the other examples of tense you give. As Yoong's sentence stands, as Noddy says, in most cases it's incorrect, or at least not useful in many circumstances (just as Noddy says). You pick nits, we pick nits.

Hi Contrex

From your reply, my conclusion is that more context is needed to make the sentence correct.

The sentence posted by me sounds unnatural without further context. Am I right in my deduction from your reply?

Many thanks.

I answered that it was perfectly "correct"



before expanding the answer by giving a real-life example of the usage of the future perfect tense.



Noddy's answer was nonsense.



What do you mean by "incorrect" exactly? Of course it's "incorrect" if you mean to say "Tom was a teacher", or "Tom will be a teacher", but if you mean to say that at a point in the future, Tom will have been a teacher, then it's the only phrase that will do. You're just repeating Noddy's nonsense, because you are more interested in contradicting me for the sake of it, in conducting arguments, and in having the last word, than you are in helping Yoong Liat with his question.



Except, as I noted, those circumstances in which it is required.

All that Noddy said, and you appear to be echoing him blindly, is that the future perfect is incorrect except when it is correct. This is, to say the least, a trivial observation.



I help people, you argue the toss.