0 the part of the body that you sit on -- 屁股
1 someone who has no home or job and lives by asking other people for money -- 乞丐
2 bad in quality or not useful -- 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。
3 to ask someone for something without intending to pay for it -- 乞讨；讨要
Could I bum a cigarette off you? 我能向你讨根烟吗？
