Translation:They are building our computer in Hungary.
Passive is rather rarely used. It's made by conjugating lenni & the adverbial participle (-va/ve, such as (meg)építve), the postposition corresponding to the English "by" in this case is által, used with the nominative, although it's even rarer.
Hungarian passive is not English-style, it's more like German or Dutch (& possibly other languages, but these are the two examples I know.) What I mean is this:
A számítógép meg van építve. = The computer has been / was built.
A számítógép meg lesz építve. = The computer will have been built.
A számítógép meg volt építve. = The computer had been built.
The way I'd think of it is that "megépülve lenni" means "having been built", as the building's already over. Tenses work accordingly.
Sentences such as "The computer is (being) built." isn't expressed with passive. Either use the active (like in the sentence in this exercise), or use another verb. Épít means to build, but épül means to be (being) built. "Épül a számítógépünk." (I'm not sure if I'd use this in this particular example, to be honest.)
In general, you can create verbs from adjectives with -ít & -ul/ül (& other ways too, I guess.)
kék = blue
kékít vmit = to turn something blue
kékül = to turn blue (intransitive)
There are also some that aren't as straightforward as this, such as épít/épül = to build / to be built (ép = intact, unharmed), pusztít/pusztul = to destroy / to be destroyed (puszta = bare) or fordít / fordul = to turn something (to translate) / to turn (we don't actually have the original word for this.)
Köszönöm a magyarázatot! :D It definitely seems that the passive voice is used far less in Hungarian, which is rather foreign to me since I'm so used to being able to use it as often as I want in all the languages I write in, but that's just something I'll have to get used to. ;)
Yes, so, basically, (I do love putting a comma after each word), basically, there is much less need for the passive voice in Hungarian since we can omit the subject from mostly any sentence. And the main reason for the passive voice is being able to avoid naming the subject. In Hungarian you just make up a regular sentence with a third person plural subject and just omit the subject.
They are bringing the soup - Ők hozzák a levest.
You cannot omit the word "they". You have to switch to passive for that. But Hungarian lets you do it, no problem:
The soup is being brought - Hozzák a levest. No need for the passive on this side.
Regarding verbs derived from adjectives, here's a nice table describing various verbs formed from colours:
(The whole book isn't available, but I think that the link should work for that page.)
For example, for fehér:
fehér, ("stative") fehérlik, ("inchoative") fehéredik/fehérül, ("causative") fehérít