Consider these two lists of words:
1. irresistible, convertible
2. comparable, breakable, stretchable
Is there any kind of rule that tells you when it is "-ible" and when it is "-able"?
And then there is likeable versus likable, and sizeable versus sizable - apparently the spelling without the E is North American.
But is always manageable, and never, ever managable, wherever in the world you are. I.e. in words ending in an E, you can sometimes drop the E when adding an -able, bit not always.
Once again, are there any rules to get through this mess? I ask because I keep on getting it wrong, and every time I have to use an -ible/-able word, I have to go look it up, and I can never seem to get them committed to memory.