广藿香的加工方法是（）

A.低温干燥 

B.晒干 

C.曝晒 

D.阴干 

E.日晒夜闷，反复至干

－How did it        that the secretary knew where we were?

－Maybe he had been following us.

A．come about

B．come across

C．come off

D．come round