"un" is a prefix in the word unsuccessful.
In the word unsuccessful, un- and suc- are both prefixes.
The suffix for "unsuccessful" is "-ful," which means "full of" or "characterized by." In this case, the prefix "un-" is added to the root word "successful" to create the word "unsuccessful," indicating the opposite or negation of success. The suffix "-ful" is commonly used to form adjectives that describe a state or quality.
I hard been trying for 3 days and have been unsuccessful
Her rebellion was unsuccessful and her daughters had been assaulted.
the cost and difficulty of such mining.
That is the correct spelling for "unsuccessful."
the Final Solution was unsuccessful.
most of them had been sunk or captured by union naval forces
The prefix is "un" while the suffix would have been "ty."
No. There has been no need for the UN to intervene in Spain.
I have been looking myself and my search has been unsuccessful. You can buy the sheet music but it is unavailable for free.