✏️
-able or -ible?
comfortable, but visible.
Grades 5-10
The rule
Use -able when the part in front is a complete word on its own. Use -ible when what is left would not be a word.
How it works
| comfortable | comfort is a word → -able |
| dependable | depend is a word → -able |
| enjoyable | enjoy is a word → -able |
| visible | vis is not a word → -ible |
| terrible | terr is not a word → -ible |
| possible | poss is not a word → -ible |
Watch out for
- This is a strong hint rather than a law. Sensible and responsible follow complete words but still take -ible.
- -able is far more common, and it is the one English still uses for new words — if you are guessing, guess -able.