Anwulf: I think you can keep "trait" as long as you pronounce the final "t" !!

Ængelfolc: yes "decided" can take an object so it is okay; I would suggest "an already-decided question" or "a yet-to-be-decided question" would make more sense though.
I googled "happened accident" and all I got was some Chinese chappie whose English needs a brush-up. Secondly "It might sound a little awkward" - that is the point - it is not normal English nor should it be. I am shielding English from outlandish inflows.

Or maybe I'm just a poor teacher!!

AEngelfolc: There are no rules; it's just a description of what happens. I do try to teach students how to write "normal" English but trying to explain why you can say "the risen Christ"; a "stricken" man; "an unexploded bomb" but not "a decided question"; "a happened accident". It's not too bad for Europeans but students from SE Asia often come up with the weirdest "English". The essential point is to be aware that "to increase" either means to become bigger or to make something bigger - that is rise or raise. As you must already know Hungarian is very picky with regard to transitive and intransitive verbs for instance keszul / keszit and often adds the causitive tat/tet suffix. English does neither except for rise/raise; fall/fell; lie/lay; sit/set and ???
I end up saying "you cannot use a passive unless the verb is transitive" , which is not quite true as there are a few verbs in English which break this "rule"; but students need some guideline to help them root out the mistakes.
Quite frankly, in my experience (!!!!) it is rare for people from SE Asia to write sound English unless they have been brought up on it from an early age; the languages and way of thinking are so different.

This: "a given name"

Ængelfolc: "In German, we say "ausgestorben", which means 'extinct' (lit. 'died out'). How could that not become an adjective? >> die out is intransitive so we cannot make up an adjective from the past participle in English, as the past participle is essentially passive in meaning which presupposes a transitive verb. There are one or two verbs such as drink >> drunken; shrink>>> shrunken which have a special form for the adjective even though the original verb has no object.

Yes the point about a thesaurus is it does not provide words which are a 100% match; it just provides words that have some overlap in meaning and/or usage, so we can't just use words from a thesaurus as stand-ins willy-nilly. Most words in a Thesaurus are a grade II match only. It's much the same when translating to a foreign tongue; the words just don't match up 100%. For example "wiped out" is not exactly the same as "died out" because it introduces the idea of someone or something killing them. To provide a more homely example: were native american bison almost wiped out or almost died out??

Wanted: teacher with ten years' jobfare.
Wanted: captain with ten years' seafaring as deck officer.
Understandable? Clear? precise? ???

I have a background in accounting and software; this is quite different from my teaching experience. Everyone has a background - it includes being raised in the Bronx or wherever, your education and so on. Even saying "teaching background" is not quite the same as teaching experience; the meaning do overlap but not 100%. And therein lies the rub. (Hamlet!). Another example I had today was "extinct" "extinction" but the verb is "die out"; one might say "dying out" for the noun but there is no real English adjective which matches extinct. Looking back thru this thread there are few "Grade I " matches; most are "Grade II" overlapping but not 100%.However there is hope: when I started teaching everyone talked about "vocabulary" but about ten years ago suddenly the jargon "in" word became "lexis" (Gk="word") - why I don't know, perhaps because someone wanted to promote the "lexical method". Anyway what is does mean is that academics (at least) can start and push change through. Now we have a new word "wordstock" that I would describe as "Grade III" that is it is understandable but not in the dictionary yet, but change is at least do-able, the real ask is what, when, and how much?
predict >>> forecast (Grade I) ?
prophesy >>> foretell (Grade II)
information >>> tidings (grade II)
experience >>> afaring (Grade IV) !!!

Wanted teacher with at least ten years' experience..
The previous ones don't make sense