How does adding an un- to a word change its meaning?

Adding the prefix "un-" to a word generally changes its meaning to the opposite of the original word.

Here's how it works:

* Negation: "Un-" essentially negates the meaning of the word it's attached to.

* Example: "happy" becomes "unhappy", "certain" becomes "uncertain"

* Reversal: In some cases, "un-" implies a reversal or undoing of an action.

* Example: "lock" becomes "unlock", "wrap" becomes "unwrap"

* Lack of: Sometimes, "un-" indicates the absence or lack of something.

* Example: "educated" becomes "uneducated", "successful" becomes "unsuccessful"

Important Notes:

* Not all words can be negated with "un-": There are some words that don't work grammatically with the prefix "un-".

* Meaning can be nuanced: While generally reversing the meaning, sometimes the nuance of the meaning changes with "un-".

Examples:

* Happy vs. Unhappy: The opposite of feeling happiness

* Tied vs. Untied: The action of undoing a tied knot

* Conscious vs. Unconscious: Lack of awareness

* Fold vs. Unfold: The opposite action of folding something

Let me know if you'd like to explore any specific examples or have more questions!