One of the most hotly debated topics in all of Klingonism, the argument over whether questions can appear as the S1 of <S1 'e' S2> constructions is one that has existed for more than ten years now. Two main schools of thought exist in the debate: one believes questions are just like ordinary sentences, and therefore we can say things like *nuq vIjatlh 'e' Dachup; the other believes that questions are grammatically distinct, and cannot be used as part of this construct.
The solution to the problem:
DloraH was informed by Marc Okrand (read part of DloraH's message below) that it is, in fact, impossible to use questions as the objects of such constructions. This means that *DaqIp'a' 'e' vISovbe' I don't know whether you hit her or not is illegal. Since DaqIp'a' is not an indicative sentence (it is interrogative), this makes sense; imperative sentences appear to be under similar restriction. (For example, yItIv 'e' vIchup is almost impossible to make sense of.)
However, for more complex sentences like nuq vIjatlh 'e' Dachup, there are two possible interpretations:
As a statement, using the question word as a relative pronoun as in English: You suggest what I say. It's not yet known whether question words can act as relative pronouns in this way; Marc Okrand also says this in his conversation with DloraH. However, it's likely that question words are just that; there is already a relative marker in Klingon, the Type 9 suffix? -bogh. In addition, on KCD Okrand used a headless relative clause (see under Relative Clauses: What Possibilities?) rather than attempt this sort of QAO, which indicates that it is probably not legal.
As a question in its own right: What do you suggest I say? There is currently no evidence for or against this interpretation, but it is probably best avoided.
At the moment, the best idea is to recast the sentence. Some examples:
For the meaning You suggest what I say: mu'tlhegh'e' vIjatlhbogh Dachup You suggest the sentence that I say.
For the meaning What do you suggest that I say?: mu'tlhegh vIjatlhnISbogh yIngu' Identify the sentence that I need to say!
DloraH's quote:
"The first one I nailed him with was our lovely QAO. Uh-oh. You can not use a 'question' as an object; but... it is not known yet if Klingon question words can act as one of those ... relative pronoun... The safest thing for now would be to recast if possible." (DloraH, personal conversation with Marc Okrand [May 1998])
This question and answer came from the KLI Wiki.