When to use -able and -ible?

This lesson tests both your vocabulary and your spelling. All the stems (the starts of words) below can have '-able' or '-ible' added to them. Can you decide whether they need able or ible? Once you have decided, try to match the word to the correct sentence. Good luck and let us know how you get on.

-able and -ible are both suffixes, groups of letters that are added to a word to change its meaning or use. When -able and -ible are added to words it generally means 'capable of being' e.g. Enjoyable: can enjoy.

-Able

-able When the root word looks like a whole word then you should be able to add able:

Enjoy + able = Enjoyable

When the stem word ends with 'e', drop the 'e' and add '-able'.

Value + able = Valuable

-Ible

-ible when the full root word is not a whole word you can add ible.

Ed + ible = Edible

Because English has plenty of irregular words, sometimes this 'drop the e rule' does not apply. All you can do is try to remember the irregular words. Many of them have a c or g before the e e.g. noticeable, changeable.

Stem Words

Predict___
Comfort___
Ed___
Poss___
Compat___
Desir___
Ador___
Access___
Respons___
Invis___

Use -ible or -able with a root word to complete each sentence. Only use each stem word once:

• 1. I am for these children so I must take good care of them.
• 2. Those berries are not , don't go near them!
• 3. The date was awful, our personalities were not at all!
• 4. You are so I knew you'd choose the chocolate!
• 5. This bed is really . I think I'll buy it.
• 6. It is really important that our cafe is so our elderly customerscan move around easily.
• 7. Is it to get to the town by bus?
• 8. I felt completely , no one talked to me the whole night.
• 9. Those handbags are expensive but very , everybody wants one.
• 10. Oh that kitten is ! Can we get one?