all of a sudden

突然

alienate, alienated, alienation, alight, align, alignment, alike, alimentary, alimentary canal, alimony, alive, alkali, alkaline, alkalinity, all, all along, all at once, all but, All Fools' Day, all in all, all one's life, all out, all over, all over again, all right, all risks, all round, All Souls' Day, all the more, all the same, all the time, all the way, all the years round, all through the night, all too, all-, all-clear, all-in, all-night, all-round,