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来源：雅诚德英语网
The first occurred in the 19th century with the creation of the first mass middle class in western Europe (see chart 1).
第一次发生在19世纪，伴随西欧首个大规模中产阶级群体产生（表一所示）。
The first occurred in the 19th century with the creation of the first mass middle class in western Europe (see chart 1).
第一次发生在19世纪，伴随西欧首个大规模中产阶级群体产生（表一所示）。