I think that's fine.

It's also used like this. For example: "During debate in the House of Representatives, Congressman Kilday, a member of the House Committee on Military Affairs, explained this provision. He stated that "while a man is in service the interest on his contract shall not exceed 6 percent per annum." Accordingly, interest in excess of six percent cannot be accrued during active service; it must be forgiven. " http://usmilitary.about.com/lib.../blchap3-7.htm

@Aiji @AlanF_US

I’ｍ not sure what the phrase "on duty" means.

I thought it meant "勤務中".
However, AlanF_US(you) says it is "兵役中"
Another possibility is "服役中".

I want to know what it is.

1. 勤務中: He is at work.
2. 兵役中: He belongs to the army.
3. 服役中: He is in jail.

Please teaching me.

He is in service.
added by an unknown member, date unknown

Based on the original sentence, this likely could have been corrected with one added word.

=> He is in THE service.
彼は軍隊にいる。 (in the service = any military service: navy, air force, army, ...)


"on duty" is closer to 勤務中: He is at work.
For example, a policeman or a guard can be on duty or off duty.

[#5070076] Lifeguards go on duty at 9:30. (CK) *audio*
[#8034399] Policemen aren't allowed to drink on duty. (CK) *audio*
Plus over 70 more.
https://tatoeba.org/eng/sentenc...e&trans_to=und

CK, thanks!
I see. It means "任務中" in a broad sense, isn't it?

Wait!

Maybe:

I think "軍隊にいる" is also right.

"任務中" means that you fulfilling the tasks and responsibilities you have been given(与えられた任務やその責任を果たす).

I see. In Japan, if you belong to the army (Self-Defense Force), you will receive a high reward. That's some difference from the background of both each country. (Of course, I'm not sure the army strictly means the Self-Defense Force...) Thanks for your detailed explanation. :)