He was a news anchorman for five years

[keannu]

My grammar book compares present perfect and past tense, saying the underlined is true, but I guess the past doesn't tell you about the present, so how can it be true that he is no more a news anchorman? Isn't it wrong? He might have come back or resumed his work, how can you be so sure a past state determines your present state?

ex)He was a news anchorman for five years -> He is no more a news anchorman now.
(in contrast)He has been a news anchorman for five years -> He is still a news anchorman now.

[Barb_D]

I"m not following your question.

You make the statement based on what you know to be true.

You know he is not currently an anchorman. You know he was an anchorman in the past. You choose your tense accordingly. Whether he might return to that job at some point in the future is irrelevant for now. He is not one now.

[bhaisahab]

My grammar book compares present perfect and past tense, saying the underlined is true, but I guess the past doesn't tell you about the present, so how can it be true that he is no more a news anchorman? Isn't it wrong? He might have come back or resumed his work, how can you be so sure a past state determines your present state?

ex)He was a news anchorman for five years -> He is no more a news anchorman now.
(in contrast)He has been a news anchorman for five years -> He is still a news anchorman now.

"He was a news anchorman for five years" this implies that he is no longer a news anchorman.
"He has been a news anchorman for five years" the implication is that he is still a news anchorman.

[keannu]

I"m not following your question.

You make the statement based on what you know to be true.

You know he is not currently an anchorman. You know he was an anchorman in the past. You choose your tense accordingly. Whether he might return to that job at some point in the future is irrelevant for now. He is not one now.

What if I don't know he is not currently an anchorman? Suppose I only know he was an anchorman and I'm explaining this to others, then there is no way to say he is not an anchorman any more right now.
In the grammar book, some part says the past never affects the present like the following.
ex) He read this book -> doesn't tell you if he is reading it even now
Then, what's the difference between this and the "anchorman" example? I see no difference except the "for" part which may assume it won't happen again.

[Tdol]

Why don't you just say what you know?

He was a news anchor for five years and may still be one.

[emsr2d2]

I agree with Tdol. If it's important that your listeners know what he does now, then find out. Otherwise, tell them you don't know.

He was a news anchor for five years. I have no idea what he's doing now.
He was a news anchor for five years and now he's a nuclear physicist.
He was a news anchor for five years. Now he's dead.

You're right that "He was..." doesn't tell you what he is doing in the present, but its use tells you what he isn't doing - he isn't a news anchor any more.

[Tdol]

If a grammatical form doesn't fit the circumstances, then don't rely on it to express your meaning- expand things and make your meaning clear. The past/present perfect is an economical way of dealing with things we know, but when we don't know, move beyond it. When we're not sure, modals are our friends.