A prefix is an added beginning to a word, which often changes its meaning.
If you add the prefix "mis" to spelled, you get the word "misspelled", which means spelled incorrectly. This is, indeed, the antonym, or opposite, of spelled.
disable, unable, and enable
in-
The prefix 'im' can added to make the word impolite.
"Possibility" doesn't have a prefix. You could add the prefix im- to it to make the word impossibility.
pre
unrational
inaddable. The prefix in is used and also the suffix Able.
You could add the prefix un- to it to make the word unreliable.
in-
The prefix "il-" can be added to "legible" to create the word "illegible," meaning not able to be read or understood.
To add a prefix to the word "definitely," you could use "in-" to form "indefinitely."
The prefix of the word is un-. The suffix of the word is -able.
Oper is the prefix. There is no suffix. Able is the root word.
You could add the prefix mis- to it to make the word misfits.
The prefix 'im' can added to make the word impolite.
Pre-The prefix for prefix is pre; because it's before the root word fix.
Monthly doesn't have a prefix. You add the prefix bi- to it to make the word bi-monthly.
"Possibility" doesn't have a prefix. You could add the prefix im- to it to make the word impossibility.