revolutions
A revolution is a successful attempt by a large group of people to change the political system of their country by force.
The period since the revolution has been one of political turmoil.
自革命以来的这一段时期是一个政治动荡的时期。
after the French Revolution.
法国大革命以后。
before the 1917 Revolution.
1917年革命之前。
A revolution in a particular area of human activity is an important change in that area.
transformation , reformation
The nineteenth century witnessed a revolution in ship design and propulsion.
19世纪经历了船舶设计和推进上的一次重大变革。
the industrial revolution.
工业革命。