There's no "that"ness or "this"ness in targh 'oH'a'? The sentence presupposes an "it" to which the speaker is linking the word targh. A better Klingon sentence meaning "Is that a targ?" would be targh 'oH'a' Ha'DIbaHvetlh'e'? or targh 'oH'a' Dochvam'e'?