Prefixes that mean not
You learn the prefixes that mean not: un-, dis-, in-, im-, il- and ir-.
How to do the test
- A prefix goes at the front of a word and changes its meaning.
- Use un-, dis-, in-, im-, il- or ir- to say not.
- Check the first letter: il- goes before l, ir- before r, im- before m or p.
A worked example
Add a prefix to make the opposite. The opposite of "visible" is ___.
- Add the prefix in- to the front of visible.
- The prefix in- means not.
- It goes before most words.
- The opposite of visible is invisible.
More examples
Add a prefix to make the opposite. The opposite of "fair" is ___.
- Add the prefix un- to the front of fair.
- The prefix un- means not.
- The opposite of fair is unfair.
Add a prefix to make the opposite. The opposite of "appear" is ___.
- Add the prefix dis- to the front of appear.
- The prefix dis- means not or the opposite of.
- The opposite of appear is disappear.
Try it yourself
Add a prefix to make the opposite.
The opposite of "regular" is ___.
Add a prefix to make the opposite.
The opposite of "polite" is ___.
Watch out
You use un- for every word, as in unpossible.
Look at the first letter of the word. Possible starts with p, so the prefix is im-: impossible.
Tips
- The spelling of the base word never changes when you add a prefix.
Why it works
A prefix goes at the front of a word and changes its meaning. These six all mean not or the opposite. The letter that starts the base word decides which one: il- before l, ir- before r, im- before m or p.