抵押合同成立于：（）
A、合同登记之日
B、签字盖章之日
C、要约到达对方时
D、合同公证之日
参考答案：B
The child has come to school by bike his own. [ ]
A. in
B. by
C. on
D. of
罂粟壳的作用是（）
A.涩肠止泻、固崩止遗、生肌敛疮
B.涩肠止泻、温中行气
C.涩肠止泻、敛肺下气、开音
D.涩肠止泻、敛肺止咳、止痛
