下列哪项符合原发性心肌病
A．炎症性心肌病变
B．肺源性心肌病变
C．原因不明的心肌病变
D．高血压引起的心肌病变
参考答案：C
This morning I had hardly got to my school when it _______ to rain.[ ]
A. had begun
B. was beginning
C. began
D. begins
国际市场上的普遍规律是( )的强势品牌占据着( )的市场。
A．20%，80%
B．30%，70%
C．40%，60%
D．80%，20%
