romuluSnganpu' HoHta' wa' nuvpu'vam'e'

one of these people killed the romulans

lugh'a' mu'tlheghvam ?

Considering further, I think you can pack nearly the entire meaning of this sentence into:

romuluSnganpu' HoHta' ngIq nuvvam.
A single one of these people killed the Romulans.

ngIq signals that the noun is either a single thing considered apart from others (what we want) or a sequence of similar things all acting in the same way. The context of whatever story you're telling would make it clear whether you meant this or These people, acting one at a time, killed the Romulans.

But this technique won't work for two of these people and so forth.

-- 
SuStel
http://trimboli.name