adv.非自愿地,非出于本意地,无意地,偶然地
Her eyes strayed involuntarily.
她的目光不由自主地移开了.
Her hands clenched involuntarily.
她本能地攥紧了拳头.
His left eyelid twitched involuntarily.
他的左眼皮不由自主地跳动。