The bridge is so important to the people here that once ________ it must be carried out without delay.

A．designs

B．having designed

C．designing

D．designed

药物按照是否需要职业医师或者职业助理医师的处方进行购买而分为（）

A.处方药非处方药

B.胶囊药片

C.中药西药

D.处方药中药