"These terms are unfortunately not precise enough."
Translation:Ces termes ne sont malheureusement pas assez précis.
I understood that long adverbs like malheureusement need to be at the beginning or the end of the sentence.
Yes, depending on the emphasis you want to give it and which word of the sentence you want to point as "unfortunate".
The "rule" I've encountered, and which did apply here, was that the adverb needs to follow the verb; so, notice that malheureusement immediately follows sont (coming before pas).
In another sentence they use "terme" as the plural for terms, but here it is marked wrong and they want "termes." Which is correct?
Is "précis" necessary? Can't this be expressed just as "Ces termes ne sont malheureusement pas assez"?
No, the meaning would be quite different:
"ces termes ne sont malheureusement pas (here you need an adjective and assez is an adverb) suffisants" = these terms are unfortunately not sufficient
Thank you very much! There's another question: will the sentence with the verb "suffire" have the same meaning? Like
"Malheuresement, ces termes ne suffisent pas"
Also, how to move" malheuresement" in the middle of the sentence above, so that the sentence would remain correct: "ne malheuresement suffisent pas" or "ne suffisent malheuresement pas"?
"ces termes ne suffisent pas" means primarily that some other terms should be added and secondarily that their content may not be exhaustive.
to add malheureusement: ces termes ne suffisent malheureusement pas.
"précis" is the common form to masculine singular and plural.
In feminine: précise, précises.