"The thing is awful!"
Translation:La aĵo estas aĉa!
From what I understand, the "-um" suffix has no independent meaning, it changes the meaning of the root to "activity/something related to 'root'" and the translation varies word to word with little or no general pattern.
Although very useful, it seems to be the only affix that can't be used as an independent word.
Wops! My mistake.
I completely forgot that "umo" is used as a translation for words with no inherent meaning.
I think that your examples show better than my comment why "umo" is an inappropriate translation for "Thing".
I'll know better than to say something just isn't possible like that in future, (I hope:P).