Actually, I think I have already said what I had to say in my response to your post about the cats and alligators. But I'll go over some of your concerns:
I think I saw from a post here that kind of said that many times,
having "descriptive adjectives" in front of UNCOUNTABLE NOUNS trigger
the need (necesssity??) to have the indefinite article "a" --
I don't think there is the need, but certainly there is the possibility:I have great faith in you.
I have a great sadness in my heart for their plight.
and I think
Mr. M said to the effect that in many cases, the choice to put "a" or
not to put it is optional for the cases like one below ("a great happiness" vs. just "great happiness")--
generally optional because both are possible; each case demands its own decision on which should be used.Here, I think
happiness is one-hundred percent uncountable
noun??, not a variable noun.--
No, we have no context, and the noun itself is capable of either form.
His dog is a great happiness in his life. (Sounds good,
isn't it? I think the writer is talking about a kind of happiness and
not the general term, happiness.) -- I agree
His dog is great happiness in his life. (Sounds good,
I think, and the writer seems to be saying that his dog is great
happiness in a general sense, not to mean any kind of happiness.) -- I don't agree. You have set up a predicate nominative. His dog has brought great happiness into his life would be fine. I leave further analysis to you.
1) So, can I say in almost all the cases, the choice to put
a or not to put a when you have some descriptive adjectives in front of
them depend on the context and perspective of the writer? -- Yes, that sounds good-- but more critical is the semantic meaning.
2) Can you give me some cases where the choices as described above in not available? -- Not offhand, but I am sure there are many-- I am sure that not all candidate nouns are capable of such permutations.
3) Can you check if these are right?
This form of words is fantastic English. -- OK
This form of words is perfectly acceptable English. -- OK
This form of words is "good" English -- OK
This form of words is a fantastic English.-- Not so.
This form of words is a perfectly acceptable English. -- Not so.
This form of words is a "good" English. -- Not so
This form of words is a regional English --
OK. English and Englishes are specific concepts in linguistics; perhaps that is why the countable form is not so attractive in your sentences. Context, flexibility, semantics.
4) Right now, I have this uneasy feeling when I try to put what look
to be descriptive adjectives in front of uncountable nouns because I am
afraid I might accidently turn them into paticular kinds of something
and not to mean generally. Do you think my feeling regarding that is
unwarranted because the control is in me whether I want to make them to
mean kinds of something or refer (or use them to mean something) in
general terms? --
Fear not; just think what you are trying to say: are you speaking of a general concept or an individual instance? and choose accordingly.
5) Can I be able to put "a" in front of uncountable nouns which have
what I think are descriptive adjectives? -- Generally yes, if you realize that it then becomes countable.
Is something in apostrophes
qualify like "good" above qualify as a descriptive adjective? -- Yes.
Help. --
I hope this did.