sleeplessness
sell, pen
SLEEPLESSNESS
The only English word you can make with those letters is oe.
The longest English word that can be made out of some of these letters is elope.
Not in the English language.
You might be looking for the word "alphabet." I realize that's eight letters.
The word that can be made using the letters in "epailcs" is "special." This word contains all the letters given and is a common English word.
There is no English word that can be made using all the letters in "yreungil."
The English words "Slay" and "Nays" are words that can be made from the letters ANSLY.
Those letters do not unscramble to a single word. Better check and see if you have given the letters correctly.
alphabet
There is not an English word obtained from the letters aazsorag.