Task: Text Simplification
Input (English): The 1930s ( pronounced " nineteen-thirties " , commonly abbreviated as the " Thirties " ) was a decade of the Gregorian calendar that began on January 1 , 1930 , and ended on December 31 , 1939 .
Output (English): The 1930s was the decade that started on January 1 , 1930 and ended on December 31 , 1939 .