"Od kiedy on jest profesorem?"

Translation: Since when has he been a professor?

[boridelf1]

Was should also be accepted, as 'since' is in the past he would have to have been a professor before.

[PinkFlowerz]

Agreed. If you accept 'since when has he been the/a professor' you need to accept 'since when was he the/a professor'. But 'Since when is he the/a professor' is the closest translation you can get.

[uranstab]

Not a native english speaker here, can it also be "Since when is he professor?"

[Jellei]

Not a native as well, but I really think it needs an article.

[schmidzy]

Correct. Unlike many other languages, English does require articles with professions.

[bluthbanana87]

You can drop the article if it's capital-P 'Professor', like a specific title of some sort rather than just a generic professor.

[WarsawWill]

When talking about time, "since" and "for" are used with Present Perfect, as in Duo's answer, not Present Simple (unlike in many languages).

It is possible to say "Since when was he a professor?", but it has a different meaning: it suggests that you don't believe he's a professor - "And since when were you such an expert on everything?"

[Kendra800150]

For me the skeptical or challenging reading is the usual pragmatic implication with the present tense as well. As someone noted below, "How long has he been a professor?" would be a more neutral formation in English, although it asks for a duration rather than a starting point.

[Kendra800150]

Returning to this a year later, I still think that "How long has he been a professor?" is the way I would ask this in English.

[Jellei]

Let's add it, then.

[Kendra800150]

Thank you! I appreciate having moderators who respond to suggestions. Some other courses seem to lack such...

[RosieDiane]

'Since when has he been a professor' is ongoing.

[Jellei]

And if he "jest profesorem", that's actually ongoing.

[RosieDiane]

Yes, I just meant that for my British English, 'has been' is more correct than 'is' in this example.

[Aran.Nelske]

Aczkolwiek, isn't "has been" past tense?

[GiacomoBia16]

"Since when has he been a professor?" sounds thousands times better ;) you should use "have been +pp/have been -ing" and "since/for" for actions started in the past but still ongoing. I guess that "He is a professor since X years" is not only weird, but definitely incorrect. Any native speaker here?

[RosieDiane]

I agree with you entirely. I am English.

[Jellei]

OK, will be the default answer now.

[SaraKos2]

Could you use present tense too? "Since when is he a professor?"

[Jellei]

We accept it, although one of our British contributors said about it:

I think only if you want it to sound incredulous/sceptical/sarcastic.
NO WAY!!! Since when is HE a professor?!

So it's probably not the greatest option.

[SaraKos2]

Ha, I guess the present tense sounds a little judgemental in America too. Thanks for clarifying!

[Hazzy56505]

Really? Since when he is a professor is wrong?

[Jellei]

An English question needs inversion: "is he".

[Firehorse1966]

Dlaczego nie mogę użyć,,since when he is a professor,,?

[Jellei]

Szyk angielskiego pytania, brakuje inwersji (he is -> is he). Typowy polski błąd, wszyscy go popełnialiśmy ;)