I think 'he is working at present' is correct - which is pretty close to your answer...
Neither 'correct solution' is an idiomatic English phrase. In English one would say: "he is working at present."
One would never say: 'presently'.
Nor would one say: 'momentarily'. And 'at the moment' is possible only in a very narrow range of contexts.
"Presently", ought to work; "momentarily", not too sure. The latter means "briefly"; or "in a bit/pretty soon". So the sense "he is at work momentarily" would convey is that he is at work but only for a short while.
"He is presently at work", on the other hand, does mean "he is at work at this moment" and would, indeed, be a correct translation.
Just wanted to add that "momentarily" does also mean "for a short time", as in "She was distracted momentarily when she noticed him in the audience, but managed to cover it up well by weaving the awkward pause into her act."
Anyway, that is another reason it would not work here.
Perhaps another situation where http://french.about.com/library/prepositions/bl_prep_en_vs_dans.htm may give a little hint, if not exact reference to this situation.
I see what you're saying. But I was thinking of a historic present context. Eg if I was explaining a novel [or a film etc] to a friend and I said "It's about a man whose wife is murdered at his home and he doesn't know about it". And my friend says "Why doesn't he know about it?" And I reply "he is at work at that moment [in the story]"
I thought French used historic present in a similar way, but I could be wrong. I wouldn't dare try to translate the above, anyhow!
Yes, historic present does exist and I have noticed in Translations on Duolingo that English speakers tend to systematically translate it in past tenses... However, in the particular perspective you propose, you could say (in real life, not on Duolingo): "il est au travail à ce moment-là".
Sitesurf, you do make me smile. :c)
I am so used to how you so kindly translate what you write in French to English so people like me can continue to learn. So I couldn't help smiling when I noticed you forgot to translate "je l'ajoute" when you translated "nous n'y avions pas pensé". I figured it out all right ("I add it") but it did give me a chuckle because such a slip was bound to happen. The way you so effortlessly switch between the two languages without losing your grounding I am surprised you don't mix the languages up more often!
Thanks for adding it. :c)
I believe "He is on the job at present." Should be accepted. I associate this usage more with jobs like construction or where there is an external job site. But it can be used more generally. It was also used on NYPD Blue to mean on duty as a police officer.
I am native speaker of English who has lived in New Orleans, London, and San Diego.
Not necessarily. Construction workers, road sweepers, truck drivers, minors, pilots are never "at the office" when they are "at work". So you cannot translate au travail to "at the office" when it is so inaccurate a translation and excludes so many professions by assuming only office jobs are considered "work".
With that negative attitude that you will never learn, you are probably right. All I know is where there is a will, there is a way. Just as you mastered your first language, or other people are fluent in several languages, French can be mastered too. Initially you may just have to commit to memory phrases you encounter and accept that they are just that way. But in time, you will come to get a feel for what is right. Don't quit at the start of the journey.