Task: Question Generation
Input (English): Context : The MG 42 (shortened from German: Maschinengewehr 42, or ``machine gun 42'') is a 7.92×57mm Mauser general purpose machine gun designed in Nazi Germany and used extensively by the Wehrmacht and the Waffen-SS during the second half of World War II. It was intended to replace the earlier MG 34, which was more expensive and took much longer to produce, but in the event, both weapons were produced until the end of the war. 
Subject : MG 42 
Relation : service entry
Output (English): In what year did MG 42 enter service?