... disagreement. The proper aim of a usage guide is to resolve these problems, rather than describe the whole of current usage. The Oxford Guide to English Usage has this aim. Within the limits just ... in topic 1.27; “l and ll” in topic 1.32; “-oul-” in topic 1.36; “-our or -or” in topic 1.37; “past of verbs, formation of” in topic 1.38; “-re or -er” in topic 1.41; “-xion or -ction” in topic ... ending in -able generally owe their form to the Latin termination -abilis or the Old French -able (or both), and words in -ible to the Latin -ibilis. The suffix -able is also added to words of...