Can anyone explain what is the difference in meaning and in use between

Hüzün
Hüzünlü
Hüzünle ??

Cok Tşk

hüzün= sadness
hüzünlü= sad
hüzünle= with sadness

a) tesadüfen, kazara ve rastlantıyla
b) sorumlu, mesul (i guess these two mean the same, the only thing is that the second one is not really turkish)
c) gizli, saklı
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a)
"Tesadüfen" is the Ottoman Turkish version of "rastlantıyla". "Tesadüf" means "rastlantı". They both mean "coincidentally".

Kazara, at most times, means the same, but its root is: "kaza", which means "accident" in English. "Kazara" is often a more negative word, meaning "accidentally", but still can be used instead of "tesadüfen" or "rastlantıyla" (or "şans eseri" etc.)

b) The meanings of "sorumlu" and "mesûl" (Note that it's not "mesül") are exactly the same. "Mesûl" is the Ottoman Turkish version and is still used expansively. (Ottoman Turkish is a much more complicated and "beautiful" version of Turkish, which is much more extensive and thus harder to learn).

c)

Gizli: Secret.
Saklı: Hidden.

they are arapçe

tesadüfen, mesul
Tesadüf and mesul and so is mesuliyet too
As so many words are mixed in both languages
Sometimes have the same meaning and a little difference in pronounciation and other times have same pronounciation but a totally different in meaning