He put varnish on the bable top to protect it, but somebody has scratched it.

他反蛋面漆油漆以保护它，但有人在上面乱画。

The simulation study shows that the electro-hydraulic servo vibration bable system, designed using the method presented here, can realize tracking control to penodic vibration test signals.

研究表明，应用这种方法设计的电液伺服振动台系统可以实现对周期或重复性的振动实验信号的跟踪控制。