-How do you keep in touch with your old classmates or schoolmates?

-By chatting with them on the Internet, _______for three hours every day. [ ]

A. approximately   

B. averagedly    

C. mostly  

D. absolutely

为使心房颤动转为窦性心律，常首选的药物为

A．洋地黄

B．胺碘酮

C．普萘洛尔

D．苯妥英钠

E．利多卡因