They want to __________ the car, but the car can't work.[ ]

A. move

B. carry

C. start

D. begin

300MW汽轮机联合汽门开启时，先开（）门，后开（）门。（）门前后压力平衡，（）门是平衡型阀门，阀体四周受力开启比较省力。