1.Hilton faced his biggest business difficulties during the Great Depression of the 1930s.
2.A lot of good rock music was created in the 1960s.
3.The Bund's big hotels look as if they were taken from 1930s New York.
請問知識大大們,上述三句都有提某個年代,為什麼前二句的年代都有加the,而第三句from 1930s New York卻沒有用the呢?謝謝。: )