Although they don’t really add to SuStel’s explanation, here are more examples of {nI’} "be long, lengthy (duration)" FYI:

   nI' DaHjaj

   Today is long. (st.k 6/29/1997)

   nI'be' yInmaj 'ach wovqu'

   Our lives burn short and bright. (Anthem)

   Qobbogh may' nI'

   long and dangerous battle (PB) [Does anyone have the full verse + translation?]

When wondering about verbs, also check how the antonym (if any) is used.  Examples of {ngaj} “be short (in duration)” :

   ngaj ram

   the night is short  (KGT)

   DaHjaj ngab wa' rep.  ngajmo' jajvam, nom bIlopnIS

   [untranslated] (MO to Lieven regarding Daylight Savings Time, 3/29/2015)

--
Voragh

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From: tlhIngan-Hol <tlhingan-hol-bounces@lists.kli.org> On Behalf Of SuStel

On 7/1/2021 8:16 AM, mayqel qunen'oS wrote:

There's the verb {nI'} "be long, lengthy (duration)"; so the question is "what does it take as a subject"?

A little bird told me, that there's the paq'batlh example of {Qobbogh may' nI' jun}, which shows that the {nI'} *can* take an event as a subject.

So, so far so good.. But this led me to wonder.. Could the verb {nI'} take as a subject the noun {poH}?

Yes, it absolutely can, because it has been used adjectivally: poH nI' long time (KGT).

It has been used other times:

yIn nI' yISIQ 'ej yIchep Live long and prosper (Radio Times)
A yIn is neither an event nor a time period.

nI' jajvam This day is long. (klingonska.org/canon/1997-06-29d-news.txt)
nI' ram The night is long. (KGT)
A day or a night might be an event or a time period, depending on how you look at it.

It seems clear to me that anything that might exist over a long duration, including time itself, can be described as nI'.

And if yes, then what would be the difference between {poH nI'} and {poH vItlh}?

vItlh is a very general verb that could be talking about the quantity or intensity of anything measurable; nI' is specifically about duration only. Your question is like asking what the difference is between a long time and a great amount of time. The latter only gets at its point indirectly.

-- 
SuStel
http://trimboli.name