Prefixes:
* Un-: To make the opposite of accomplish, meaning "not accomplish" or "fail". Example: unaccomplished.
* Over-: To emphasize the extent of accomplishment, meaning "accomplish beyond expectations". Example: overaccomplish.
* Re-: To indicate repeating the act of accomplishing, meaning "accomplish again". Example: reaccomplish.
* Mis-: To indicate a mistake in accomplishing, meaning "accomplish incorrectly". Example: misaccomplish (though less common).
Suffixes:
* -ment: This suffix can be used to turn verbs into nouns, but it's not typically used with "accomplish".
Alternatives:
* You can use prefixes and suffixes with related words:
* Achieve: unachievable, overachieve, reachieve
* Complete: incomplete, overcomplete, recomplete
* Succeed: unsuccessful, oversucceed, resucceed
The best choice depends on the context and the specific meaning you want to express.