怠速控制装置常采用节气门直动式和（）
A.节气门旁通气道式
B.步进电机式
C.旋转滑阀式
D.节气门被动式
参考答案：A
It’s very important for a student to ___ a good state of mind while taking the college entrance examination.
A keep out B keep on C keep up D keep off
红细胞叠连的主要影响因素主要在血浆。()
