a.
1.
Humorsome, capricious, variable.
2.
Angry, petulant, irritable, irascible, passionate, snappish, pettish, sour, crusty, crabbed, waspish, captious, snarling, peevish, testy, fretful, ill-tempered, out of humor, out of temper.
3.
Sullen, perverse, wayward, sulky, humorsome, glum, grum, glowering, morose, spleeny, frowning, stubborn, dogged, intractable, cross-grained.
4.
Gloomy, melancholy, sad, pensive, abstracted, saturnine.