"Is the Klingon's name Torg?"
Translation:torgh 'oH'a' tlhIngan pong'e'?
Putting two nouns next to each other indicates a kind of possessive relationship, tlhIngan pong is “the Klingon’s name” (or “a Klingon’s name”, “a Klingon name”, etc.).
For “NOUN1 is NOUN2” sentences, you join the two nouns with a pronoun, e.g. 'oH for an inanimate, singular subject, and mark the subject with the suffix -'e'.
So torgh 'oH tlhIngan pong'e' is “The Klingon’s name is Torg.”
Then to turn that into a yes-no question, you add the verb suffix -'a' to the pronoun 'oH: torgh 'oH'a' tlhIngan pong'e'? “Is the Klingon’s name Torg?”
When you have two nouns next to each other, they can be used together as a subject or an object without any special markings and they can be used as a location by using the locative markers. No -'e' is need for noun-noun, unless the -'e' is being added for some other purpose.
For instance I can say, 'IH tlhIngan pong ("The Klingon's name is pretty.") and no -'e' is needed.
In this Duolingo sentence the -'e' is required because we are using a special sentence form which uses a pronoun ('oH) as if it were the verb "to be". In this special kind of sentence, the subject is always marked with the topic suffix -'e' whether it's a simple one word noun or a complicated noun phrase. Compare:
torgh 'oH ("It is Torg.")
torgh 'oH pong'e' ("The name is Torg.")
torgh 'oH tlhIngan pong'e' ("The Klingon's name is Torg.")
"O nome do klingon" translated to English can be "the name of the Klingon", but you can also use the possessive s: "the Klingon's name". Klingon does it more like that second English version, but doesn't even have any marker (like the English possessive s). Any time two nouns are directly adjacent (and not part of two separate clauses or part of a list followed by a conjunction) the last noun is the thing being talked about and the noun before it is the type or posessor of that thing. baS betleH "bat'leth de metal", vulqangan Duj "navio Vulcan", tlhIngan pong "o nome do klingon".
Now you can plug that noun phrase into a simple "to be" sentence: torgh 'oH tlhIngan pong'e' "O nome do Klingon é Torg."
Finally, you can use the interrogative marker to make it a question. Since 'oH is acting like a verb you can put verb suffixes on it: torgh 'oH'a' tlhIngan pong'e' "O nome do Klingon é Torg?" But in English to make this a question, we have to switch the verb and subject: "Is the Klingon's name Torg?"