observance

n.仪式，习惯

obliviousness, oblong, obloquy, obnoxious, obnoxiously, obnoxiousness, oboe, oboist, obscene, obscenely, obscenity, obscur, obscure, obscurely, obscurity, obsequies, obsequious, obsequiously, obsequiousness, observable, observant, observantly, observation, observation car, observation post, observatory, observe, observer, observing, obsess, obsessed, obsession, obsessional, obsessive, obsessively, obsolescence, obsolescent, obsolete, obssess, obstacle,