造成再生障碍性贫血最主要的原因是
A．造血原料不足B．长期营养不良C．脾功能亢进D．骨髓造血功能衰竭E．急性大量失血
参考答案：D
Don’t call him at this time tomorrow, because he ________ a meeting with his teachers.
A．is having
B．is going to have
C．will be having
D．has been having
BZZ20803电源系统当（）和（）时BFU中的直流接触器切断负载。
