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major powers of the world; great powers
日本は列強入りを目指した。
Japan aimed to join the ranks of the great powers.
列強の圧力に小国は苦しんだ。
Smaller nations suffered under the pressure from the great powers.
19世紀は列強が世界を支配した時代だった。
The 19th century was an era when the great powers dominated the world.