In English, the suffix -able turns verbs into adjectives meaning 'can be done' or 'fit for'. 'Wash' (verb) becomes 'washable' (adjective — can be washed). 'Break' becomes 'breakable' (can be broken). 'Read' becomes 'readable' (can be read, or easy to read). 'Move' becomes 'movable' (can be moved). 'Enjoy' becomes 'enjoyable' (can be enjoyed). The basic rule: verb + able = adjective. Most verbs just add -able. Verbs ending in silent -e drop the -e (move + able = movable). Verbs ending in -y change to -i (rely + able = reliable). The -able adjective usually means 'can be done' or 'has the quality of being'. Once students know the pattern, they have access to many useful adjectives. -able is one of the most productive adjective-forming suffixes in English. This lesson is part of the suffix family — covered more broadly in adjective suffixes (#28) and pairs with -ness (#86) and -ment (#91).
Before you start — think honestly about your own teaching and experience.
Look at the examples. Answer each question before reading the explanation — this is how your students will learn too.
wash (verb) → washable (adjective): The shirt is washable.
break (verb) → breakable (adjective): The vase is breakable.
read (verb) → readable (adjective): The book is readable.
comfort (verb/noun) → comfortable (adjective): The chair is comfortable.
use (verb) → usable (adjective): The phone is still usable.
fit (verb) → fitable (less common — 'suitable' is more common)
What does the -able suffix mean? Why is it useful?
-able is a very productive adjective-forming suffix in English. It takes a verb and turns it into an adjective meaning 'can be done' or 'has the quality of being'. Wash + able = washable (can be washed). Break + able = breakable (can be broken — fragile). Read + able = readable (can be read, or easy to read). Use + able = usable (can be used, working). The basic rule: verb + able = adjective. Once students know the pattern, they can build many adjectives from verbs they already know. Vocabulary expansion through -able is one of the most useful word-building skills. Common useful -able adjectives appear in everyday and formal contexts: washable clothes, breakable items, comfortable chair, valuable possessions, reliable workers, enjoyable evening.
Most verbs just add -able:
wash → washable, break → breakable, read → readable, comfort → comfortable, eat → eatable
Verbs ending in silent -e drop the -e:
move → movable (drop the e)
use → usable (drop the e)
love → lovable (drop the e)
BUT some keep the e:
like → likeable OR likable (both correct)
notice → noticeable (KEEP the e — to keep the soft c sound)
change → changeable (KEEP the e — to keep the soft g sound)
Verbs ending in -y change y to i:
rely → reliable (y to i)
enjoy → enjoyable (y stays — y is after a vowel)
comfort → comfortable
Why do these spelling rules matter?
The spelling rules for -able are important for accuracy. Most verbs just add -able with no change. Verbs ending in silent -e usually drop the -e (move → movable). But some keep the -e to preserve the pronunciation — 'noticeable' keeps the e because without it, 'noticable' would have a hard c sound (like 'k'). The e keeps the soft c sound. Same for 'changeable'. Verbs ending in -y after a consonant change y to i (rely → reliable). Verbs ending in -y after a vowel keep the y (enjoy → enjoyable, employ → employable). The y-to-i rule is the same as for plurals (#11), third-person -s (#76), and -ness suffix (#86). Knowing one rule helps with all the others. Drilling the spelling prevents the most common errors.
-ABLE (adds to verbs you can recognise):
wash → washable
break → breakable
read → readable
enjoy → enjoyable
-IBLE (often with words from Latin — harder to predict):
possible (NOT possable)
visible (NOT visable)
edible (NOT edable — meaning 'can be eaten')
incredible (NOT incredable)
sensible (NOT sensable — meaning 'showing good judgement')
How can students choose between -able and -ible?
-able and -ible are very close — both turn words into adjectives meaning 'can be'. The difference is mostly historical. -able is added to verbs from English roots (wash, break, read, move). -ible is added to words from Latin roots (possible, visible, edible, sensible). For students, the simpler approach: when they can recognise a clear English verb, the suffix is usually -able (washable, breakable). When the word feels Latin or scientific, it might be -ible (possible, visible, edible). But there is no perfect rule — students must memorise the most common -ible words: possible, visible, edible, sensible, incredible, terrible, horrible. For the lesson focus, -able is more productive — students can build many words with it.
| Pattern | Description | Examples | Notes |
|---|---|---|---|
| Verb + ABLE | Basic rule — most verbs | wash → washable, break → breakable, read → readable, eat → eatable, work → workable | Just add -able. No spelling change. |
| -E drops | Most verbs ending in -e drop it | move → movable, use → usable, love → lovable, value → valuable, like → likeable | Drop the -e before -able. |
| -E stays | Some verbs keep -e for pronunciation | notice → noticeable (keeps the e to keep soft c), change → changeable (keeps the e for soft g) | The e stays to preserve sound. |
| -Y to -I | After a consonant | rely → reliable, deny → deniable, satisfy → satisfiable | Y to i before -able for consonant + y. |
| -Y stays | After a vowel | enjoy → enjoyable, employ → employable | Y stays for vowel + y. |
| Common useful -able adjectives | Words students should know | washable, breakable, readable, comfortable, valuable, reliable, enjoyable, available, suitable, capable, portable, profitable | Useful everyday vocabulary. |
| -IBLE vs -ABLE | Different suffix for some words | -ABLE: washable, breakable (English roots) | -IBLE: possible, visible, edible, sensible (Latin roots) | Memorise common -ible words. -able is more productive. |
PATTERN 1 — The basic rule: For most verbs, just add -able to make the adjective. Wash + able = washable. Break + able = breakable. Read + able = readable. Most verbs follow this pattern with no spelling change.
PATTERN 2 — Drop the -e: For verbs ending in silent -e, drop the e before -able. Move + able = movable (drop the e). Use + able = usable. Value + able = valuable. The e is removed.
PATTERN 3 — Keep the -e for pronunciation: A few verbs keep the -e to preserve a soft sound. Notice + able = noticeable (keep the e to keep soft c). Change + able = changeable (keep the e for soft g). Manage + able = manageable. The e stays.
PATTERN 4 — Y to I rule: Verbs ending in -y after a consonant change y to i. Rely + able = reliable. Deny + able = deniable. The same y-to-i rule as for plurals (#11), third-person -s (#76), and -ness (#86).
PATTERN 5 — Y stays after vowel: Verbs ending in -y after a vowel keep the y. Enjoy + able = enjoyable. Employ + able = employable. The vowel before y means y stays.
PATTERN 6 — -able for verbs you recognise: Most -able adjectives are built from English verbs (wash, break, read, move, use, enjoy). When students can recognise the verb, -able is usually right.
PATTERN 7 — -ible for Latin-origin words: Some adjectives use -ible instead of -able. Possible, visible, edible, sensible, incredible, terrible, horrible. These are mostly from Latin roots. Students must memorise the common -ible words. -able is more productive for new word-building.
The -able suffix is essential for vocabulary expansion. Once students know the pattern, they have access to many useful adjectives describing what can be done. The lesson connects to other suffix lessons — adjective suffixes (#28) for the broader treatment, -ness (#86) for nouns from adjectives, -ment (#91) for nouns from verbs. Together they cover the main word-building suffixes. Students who know the suffix family can build hundreds of new words from verbs and adjectives they already know.
Build an -able adjective wall with verb-adjective pairs. Wash/washable. Break/breakable. Read/readable. Move/movable. Drill the pattern through speed practice — call out a verb, students give the -able adjective. Practise the spelling rules — drop the -e, change y to i, keep the e for pronunciation. Speed forces automatic recall.
Choose the correct -able adjective form. Apply the spelling rules.
Each sentence has an -able spelling error. Find the wrong form, write the correct one, and explain.
Use this sequence directly in class — guided discovery, no textbook needed. Tap each step to mark it done.
STEP 1 — What -able does (5 min): Write 'wash' on the board. Add -able to make 'washable'. Show that -able turns verbs into adjectives meaning 'can be'. The verb wash becomes the adjective washable (can be washed). Establish the basic pattern.
STEP 2 — The basic rule (5 min): Drill the basic pattern. Most verbs just add -able. Wash + able = washable. Break + able = breakable. Read + able = readable. Practise five examples. The pattern is simple and productive.
STEP 3 — The -e rule (6 min): Drill the e-dropping rule. Most verbs ending in -e drop it: move → movable, use → usable, value → valuable. But some keep the e for pronunciation: notice → noticeable, change → changeable, manage → manageable. Show examples of both.
STEP 4 — The y rule (5 min): Drill the y rule. Y after a consonant changes to i: rely → reliable, deny → deniable. Y after a vowel stays: enjoy → enjoyable, employ → employable. The same y-to-i rule from other lessons.
STEP 5 — -able vs -ible (4 min): Briefly cover the -ible exception. Some words use -ible (not -able): possible, visible, edible, sensible, incredible, terrible, horrible. Memorise these common -ible words. -able is the more productive suffix for new word-building.
Use directly in class — copy, adapt, or read aloud. No printing needed.
For each strategy, choose the option that best describes where you are now.
Your feedback helps other teachers and helps us improve TeachAnyClass.