From the discussions of another lesson I learned that the difference between şimdi and artık is that the first means right now, but perhaps not tomorrow, while the latter means from now on and at least some time. So shouldn't it be O artık asker?
"His is soldier" is simply wrong English. When stating your profession, you must have an article before it. There only exceptions are when you are stating an official title, such as "I am President." :)