The word "Feedback" in context and Grammar check

[flin8812]

(1)
Feedbacks from any faculty/faculties(?) are welcomed.
(should this be in plural, and why?)
(2)
Feedback (As a title, should it be plural or noun ? Why?)
I would like to see the guidelines from previous years to be made available on the website.
(3) A negative feedback OR Negative feedbacks

Is there a more comprehensive way of understanding when and which situation plurals may be applied.

[Raymott]

(1)
Feedbacks from any faculty/faculties(?) are welcomed.
(should this be in plural, and why?)
No, it's always singular. It's like 'advice'; it's a non-count noun.
(2)
Feedback (As a title, should it be plural or noun singular ? Why?)
It's always singular.
I would like to see the guidelines from previous years to be made available on the website.

(3) A negative feedback OR Negative feedbacks
'Some negative feedback.'
Is there a more comprehensive way of understanding when and which situation plurals may be applied.
For 'feedback'? It's always singular.

R.

[flin8812]

so just to reiterate what you have said and put it into direct use... (<--please correct me if I'm not suppose to use 'it' here)
If I have the word "advice" in a sentence, then should I say
" Could you give me an advice/feedback "
OR
" Could you give me some advice/feedback" (despite both advice and feedback are singulars)

Also, does this mean that words like "suggestion" and "opinion" are non-countable nouns regardless of situation.

Thanks again

[Raymott]

so just to reiterate what you have said and put it into direct use... (<--please correct me if I'm not suppose to use 'it' here)
If I have the word "advice" in a sentence, then should I say
" Could you give me an advice/feedback " No
OR
" Could you give me some advice/feedback" (despite both advice and feedback are singulars)
This one. When I said, "It's always singular", I meant it's never 'feedbacks/advices". I should have said it's a non-count noun, like 'water'.
It's "Give me some water", not "Give me a water" and not "Give me waters".
('Water' can be plural, but not in its usual meaning.)
Also, does this mean that words like "suggestion" and "opinion" are non-countable nouns regardless of situation.
No, unfortunately it doesn't mean that. You have to learn which ones are non-countable. There should be lists somewhere that you can search for -
"non-count nouns", "noncount", non-countable" etc.
Thanks again

R.