给定一个英文段落，自动提取段落中的关键词和它们的出现次数。


The industrial revolution was a period in the late 18th and early 19th centuries when major changes in agriculture, manufacturing, and transportation had a profound effect on socioeconomic and cultural conditions in Britain and subsequently spread throughout Europe and North America and eventually the world.
关键词: industrial revolution, late 18th century, early 19th century, agriculture, manufacturing, transportation, socioeconomic, cultural conditions, Britain, Europe, North America, world. 

它们的出现次数: 

- industrial revolution: 1 
- late 18th century: 1
- early 19th century: 1
- agriculture: 1
- manufacturing: 1
- transportation: 1
- socioeconomic: 1
- cultural conditions: 1
- Britain: 1
- Europe: 1
- North America: 1
- world: 1