In Power Klingon {-chu’} is described as a qualifying suffix which "indicates action is performed absolutely properly."  In other words, it’s used on action verbs.  Adjectival verbs (which Okrand calls “qualities”) are states of being, not actions, e.g. {Doq} “be red”.  To turn a quality into an action you need to add a suffix, i.e. {-moH} “cause” or {-choH} “become”.

 

{'eychu'bogh chab} doesn’t work because {'ey} “be good/delicious/tasty” is also an adjectival verb – even with {-bogh} – and doesn’t take {-chu’}.

I don't think Okrand was trying to make the distinction between actions and states here. He chose the word action instead of verb because he's speaking to the layman. I think 'eychu'bogh chab is perfectly legal.

There is an instance of -chu' on a quality verb in paq'batlh: qatlh Sutamchu' tlhIH Why are you all silent?

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SuStel
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