高压油泵并不直接控制喷油，它的任务仅仅是向高压（）供油以便维持所需的共轨油压。
A.喷油器
B.高压油管
C.共轨油管
D.喷油泵
参考答案：C
不属于非特异性免疫细胞的是
A．NK细胞
B．肥大细胞
C．中性粒细胞
D．B1细胞
E．B2细胞
-I joined the League _____ May 4th, 20ll. What about you
-I have been a League member ______ three years ago.
A．in; for
B．on; for .
C．in; since
D．on; since
