一般门诊处方应开（）
A．SDA
B．BP
C．JP
D．USP
E．WHO
参考答案：B
I was really anxious about you.You _____ home without a word. [ ]
A. mustn't leave
B. shouldn't have left
C. couldn't have left
D. needn't leave
本票是付款承诺，无需承兑，其出票人始终足主债务人；汇票需要经付款人承兑，承兑后承兑人成为主债务人，出票人降为从债务人。( )
