The suffix -bar is often used with transitive verbs:
Suffix, durch dessen Anfügen an den Stamm eines meist transitiven Verbs ein Adjektiv abgeleitet wird [...] (from German Wiktionary: -bar)
For example:
avoidable - vermeidbar → vermeiden (transitive)
vulnerable - verwundbar → verwunden (transitive)
reliable - verlässlich → verlassen ([in this case] intransitive)
movable - beweglich → bewegen (intransitive)
A verb is transitive if you can use it for something or someone:
Jemanden sehen, etwas lösen, etwas haben
And intransitive if you can't:
Laufen, scheinen, dünken
Note that this is really just a rule-of-thumb; it doesn't necessarily work 100 per cent of the time (though I can't think of a verb where it fails now). :)
The English -ible versus -able seems to work differently:
The form -ible has the same senses and pronunciation. The choice between the two is somewhat idiosyncratic, but in general, -ible is used in forms derived from Latin verbs of the second, third, and fourth conjugations, and in a few words whose roots end in a soft c or g, while -able is used in all other such words, particularly those formed from Latin verbs of the first conjugation and those that come from French or from Anglo-Saxon (Old English). (from Wiktionary: -able)
Note tohuwawohu's great comment:
... For example, a locomotive can move "itself", but i (personally) can't move it myself, so it's beweglich but (from my point of view) not bewegbar. See also here and here.
solvable
:= löslich? Solvable coffee?usable
:= nützlich? I would translatenützlich
touseful
, notusable
.