石棉引起的法定职业肿瘤为（）
A.白血病
B.直肠癌
C.肺癌
D.间皮瘤
E.肺癌、间皮瘤
参考答案：E
Teaching is a difficult job ______ requires great skill and patience．
A．which
B．where
C．who
D．why
既能补血，又能止血的药物是()
A.当归
B.大枣
C.大蓟
D.阿胶
