These two notes about "questions as objects" actually raise a large number
of issues, so this will end up being a stretched-out (over time) response.
But here's a start.
All four words asked about (tul "hope," Qub "think," Sov "know," and SIv
"wonder") can be used in the construction S 'e' V, where S is a sentence,
'e' is the pronoun ("that") which refers to a previous topic (in this case
S), and V is one of the verbs listed above (as well as some others).
If the sentence (S) is tlhIngan Hol Dajatlh "you speak Klingon" (tlhIngan
Hol "Klingon language," Dajatlh "you speak it"), it's OK to say:
tlhIngan Hol Dajatlh 'e' vItul "I hope that you speak Klingon"
(vItul "I hope it")
tlhIngan Hol Dajatlh 'e' vIQub "I think that you speak Klingon"
(vIQub "I think it")
tlhIngan Hol Dajatlh 'e' vISov "I know that you speak Klingon"
(vISov "I know it")
tlhIngan Hol Dajatlh 'e' vISIv "I wonder if you speak Klingon"
(vISIv "I wonder it")
The fourth example is weird from an English translation point of view, but
it falls right in line in Klingon. If the English translation matched the
pattern of the other three sentences, it would be "I wonder that you speak
Klingon." In English, this means something like "I'm surprised that you
speak Klingon" or "I don't understand how it can be that you speak
Klingon," but this is not what the Klingon sentence means. The Klingon
sentence means something more like "I am curious about whether you speak
Klingon." The clumsiness here is the English, not the Klingon.
One other verb that can be used in the V slot in such sentences is Hon
tlhIngan Hol Dajatlh 'e' vIHon "I doubt that you speak Klingon"
(vIHon "I doubt it")
I'll return on another occasion to the question of whether the sentence
preceding the 'e' in such sentences can be a question. This is a more
general issue than whether you can do it with SIv "wonder" and I need some
clear guidance from Maltz.