Sandy _____ her homework in the study now. [ ]
A. does
B. is doing
C. do
D. to do
答案:B
生石灰的等级共分为三级。
下列哪一项符合下壁Q波心肌梗死的心电图改变()
A.V1~V3导联宽而深的Q波形成
B.V7~V9导联宽而深的Q波形成
C.Ⅱ、Ⅲ、aVF导联宽而深的Q波形成
D.V3R~V6R导联宽而深的Q波形成
E.I、aVL导联宽而深的Q波形成