在合模过程中,如有由于模具间有异物或导柱和导套配合不好,可采用()合模加以保护。
A.快速
B.低速
C.低压
D.高压
参考答案:C
_______ such heavy pollution already, it may now be too late to clean up the river. [ ]
A. Having suffered
B. Suffering
C. To suffer
D. Suffered
干式自动灭火系统适宜在不高于80℃的环境使用。