坏账损失
参考答案:
因债务人破产或者死亡,以其破产财产或者遗产清偿后,仍然不能收回的应收帐款,或者因债务人逾期未履行偿债义务超过3年然仍然不能收回的应收帐款。
The boy on the playground ____ be Tom, because he saw him in the library just now.
A.must
B.can't
C.can
D.might
离子通道运输