【多选题】有关 RNA 病毒叙述中正确的是
E.
负链 RNA 病毒携带依赖 RNA 的 RNA 多聚酶
【单选题】An annoying vibration can be caused at the natural resonance of the car's engine mount ______.
A.
if the engine moves too fast
B.
if the engine's amplitude increases
C.
if a tire gets out of balance
D.
if a damage occurs in the engine
【多选题】The main parts that make up a car engine are()
【判断题】从数控(CNC)伺服控制系统的控制方式来看,伺服控制系统有开环控制系统、半闭环控制系统、闭环控制系统。()
【单选题】The engine of a good car is expected to run ______.