bumming/bʌm/形容词劣质的;无用的He gave us bum directions, but we eventually found the place.他给我们指错了路,但是我们最后还是找到了那个地方。/bʌm/动词乞讨;讨要Could I bum a cigarette off you?我能向你讨根烟吗?/bʌm/名词屁股乞丐想跟读,去练习