热室压铸机生产时，熔化锌合金温度应控制在（）之间。
A、300°～400°C
B、400°～420°C
C、500°～600°C
参考答案：C
The Great Wall travel _______deep valleys, ________deserts and ________mountains.
A．over, across, through
B．through, over, across
C．across, through, over
D．through, across, over
治疗肾阴虚型崩漏的首选方剂是（）
A.金匮肾气丸
B.二仙汤
C.左归饮
D.右归丸
E.左归丸合二至丸
