Table vs. Comfortable: Same "-able" Ending, Completely Different Vowel
Table, cable, comfortable, reasonable — all four end in the same four letters, -able. A lot of learners quietly assume that string is pronounced the same way every time, and either flatten table into a mumble, or stretch comfortable with a syllable that was never supposed to be there.
It's not random. Those four letters actually mark two completely different situations, and the vowel that goes with them is different in each.
Case 1: -able is a suffix, tacked onto a word that already exists on its own
Comfortable = comfort + able. Reasonable = reason + able. Acceptable = accept + able. Washable = wash + able. Available = avail + able. Strip off -able, and what's left is a real, standalone word.
Whenever that's true, -able is an unstressed suffix, and its vowel collapses into a schwa /ə/ — the same reduction rule as everywhere else in English:
- comfortable /ˈkʌmftəbl/ — the stress sits on comfort, -able is almost inaudible
- reasonable /ˈriːznəbl/
- acceptable /əkˈseptəbl/ — the stress sits on -cept, -able still reduces
- washable /ˈwɒʃəbl/
- available /əˈveɪləbl/
No matter where the stress lands on the word in front of it, -able itself is never stressed, and it never gets the full diphthong /eɪ/.
Case 2: -able isn't a suffix at all — it's just how the word happens to be spelled
Table, cable, stable, fable, gable — strip off -able here, and what's left (t-, c-, st-, f-, g-) isn't a word. These aren't built from a root plus a suffix. The -able has been part of the word from the start.
In this group, the a is the stressed syllable, and it gets the full diphthong /eɪ/:
- table /ˈteɪbl/
- cable /ˈkeɪbl/
- stable /ˈsteɪbl/
- fable /ˈfeɪbl/
- able itself: /ˈeɪbl/
A test you can run instantly: remove -able and check whether what's left is a word you actually recognize on its own. If it is, that's the suffix — say /əbl/. If it isn't, -able is just the word's spelling — say the full /eɪbl/.
-ible is simpler: it's almost always the suffix
Visible, possible, terrible, horrible — strip off -ible and what's left (vis-, poss-, terr-, horr-) isn't quite a standalone modern English word, but -ible in English is reliably a suffix. The rule holds steady: always unstressed, never /aɪbl/.
- visible /ˈvɪzəbl/
- possible /ˈpɒsəbl/
- terrible /ˈterəbl/
- horrible /ˈhɒrəbl/
There's one famous exception, and it's a good one for breaking the pattern: Bible. It ends in the same four letters, i-b-l-e, but it isn't built from any root plus a suffix — it's a complete word on its own (from Greek biblia). So Bible is stressed, with the full diphthong: /ˈbaɪbl/, not remotely like visible. If you assume every "-ible" ending is automatically weak, Bible is the first word that will catch you out.
The takeaway: if -able or -ible peels off to reveal a real, independent word, it reduces to /əbl/. If it doesn't — if the ending is just how the word is spelled — it stays full and stressed, as /eɪbl/ or /aɪbl/.
Not sure whether an -able or -ible word should be stressed there or reduced? PHONO reads any English text through your camera and marks every word with IPA, stress included, with both US and UK audio.
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