We learnt three important facts today about the suffixes ible and able:
1. Most words ending in –ible don’t have an obvious root word:
vis + ible = visible
terr + ible = terrible
2. Most words ending in –able do have an obvious root word:
consider + able = considerable
reason + able = reasonable
3. More words end in –able than – ible.
These facts can help you to work out whether to use –ible or –able.
A root word is what is left when any prefixes and suffixes have been removed and it makes sense on its own.
uncomfortable un + comfort + able
Sometimes we cannot see or hear a complete root word when prefixes and suffixes have been removed, for example:
impossible im + poss + ible
The root is from the Latin word possibilis, which means ‘that can be done’, so it doesn’t have a whole English root word.
If you have a whole root word left when you take away the ending, the chances are quite high that the ending should be –able.
But beware! There are some words that don’t follow the pattern.
The root words:
have the ending –ible: