"Where is the bathroom?"
Translation:nuqDaq 'oH puchpa''e'?
The suffix -'a' is not a question mark. It specifically turns a statement into a question. "Where is the bathroom" was never a statement to begin with and so doesn't get the -'a'. I can take the statement naDev 'oH puchpa''e' ("The bathroom is here") and turn it into the question naDev 'oH'a' puchpa''e' ("Is the bathroom here?"), but when I add the question word nuqDaq ("where"), it doesn't take the -'a' suffix any longer.
Note that when I stated the location of the bathroom as a sentence, I still included the suffix -'e'. These two suffixes are completely unrelated. The interrogative suffix -'a' is a verb suffix and should go on the verb. The "topicalizer" suffix -'e' is a noun suffix and should go on a noun. This might also be a good time to mention that there is a separate noun suffix -'a' that has a completely different meaning that you will learn about later.
The noun suffix -'e' drawns attention and focus to the noun it is marking and is often best interpreted with the phrase, "as for the..." In this sentence that might wind up with the translation, "As for the bathroom, where is it?" In most sentences it is completely optional to use the -'e'. However, Klingon grammar requires that when you use a pronoun as a copula (in other words, using it to link two noun phrase, like we use "to be" in English sometimes), you must use -'e' to mark the topic of the copula.
Sometimes we don't actually state the topic. Like if you asked if I needed to use the bathroom and I answered, HIja'. nuqDaq 'oH? ("Yes. Where is it?). Context makes it clear what "it" I am talking about, so I don't need to repeat the topic. But if we were talking about something else, I would need to state it and then -'e' is required: nuqDaq 'oH puchpa''e'? ("As for the bathroom, where is it" or simply "Where is the bathroom?")
I hope that has helped. I thought we had explained this in the Tips & Notes. Have you been reading the Tips & Notes? If you have not been reading the Tips & Notes, I would like to ask that you review those so we don’t have to continuously repeat the information that we have explained there.
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If you click on the light bulb it will reveal the Tips & Notes and give you a detailed explanation of the grammar that is introduced in that Skill. If you have questions after reading the Tips & Notes for the previous and current Skills, then please return to the forum to ask your question, explaining what you didn’t understand or what seems contradictory to you.