A trial run is needed before the machine is put into operation.
A.机器投入运行前,须先行试车。 B.机器投入运行前,须先行做实验。 C.试车前,须先投入机器。 D.试车前,须先操作机器。正确答案A
A trial run is needed before the machine is put into operation.
A.机器投入运行前,须先行试车。 B.机器投入运行前,须先行做实验。 C.试车前,须先投入机器。 D.试车前,须先操作机器。正确答案A