"Often, I am a man."
Translation:Gyakran vagyok férfi.
Well... This goes so far. There is a famoous poem of Attila József, one of the most revered poets of Hungary that goes something like that: "You know there is no forgiveness. / therefore there's no use being sorry / Be as you are, a [real] Man / and the grass will grow behind you" ("Tudod, hogy nincs bocsánat, / hiába hát a bánat. / Légy, aki lennél: férfi / s a fű kinő utánad")
Though this is a well-known and often cited verse, this is not obvious even for us, Hungarians. :D It's meaning is fading and most people won't really know what is this about. (There is no use to lament on the old mistakes because nobody will actually give you a relief. So be a rightful and honest man, and you will have a grave that will be not exactly cared after but at least not spoiled.)
Often, I am a man. Gyakran vagyok férfi. —I try to be honest and keep my name clean. --> Often I am a man. Not always because we are weak and prone to the temptations, but well, I am quite often a Man.
If you see this way, the sentence tries to form some reason. :D
Now, let's see the indefinite article. We use them a bit differently than the English and even more differently than the romance languages. In this situation it is completely unnecessary in Hungarian. Using it would alter the meaning of this sentence to an even less meaningful one: Often I am one certain but not specified man. The definite article would create another strange sentence that means that Often I take the man's role. Without the indefinite article it is something theoretical, like in the poem above.
Note that it took me some two years or more to realize this layer of its meaning. This sentence is creepy in a lang course :D