第三十期答案如下 1-20 cabbc baaca ccbca babcb 21-40 cdbdb bcadd bcdcc cadbb 41-60 cdaba cbdac acdbd bcddc 61-75 badad ccdab cbadc 76.of变为from 77.absorbing变为absorbed 78.over变为to 79.up变为dowm 80....