具有体内、外抗凝血作用的药物是（）
A.肝素
B.维生素K
C.铁剂
D.叶酸
E.维生素B12
参考答案：A
What a pity! The little girl had to drop out of school and _____ the responsibilities that
most parents can take, after her parents passed away in the earthquake. [ ]
A. take on
B. take in
C. take off
D. take after
十九世纪30 年代，下列拉美地区中除了哪一个国家外均已独立？[ ]
A．古巴
B．海地
C．巴西
D．墨西哥
