In this task, we ask you to elaborate the sentence without changing its general meaning. You can do so by explaining further the input sentence, using more precise wording, adding qualifiers and auxiliary information etc.
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Question: In marine sediments methane is produced when sulfates are low .

Answer: In marine sediments the biological production of methane , also termed methanogenesis , is generally confined to where sulfates are depleted , below the top layers .


Question: The zlib License is an open source software license .

Answer: The zlib license has been approved by the Free Software Foundation ( FSF ) as a free software license , and by the Open Source Initiative ( OSI ) as an open source license .


Question: Immanuel Maurice Wallerstein ( ; September 28 , 1930 – August 31 , 2019 ) was an American sociologist , economic historian and world-systems analyst .

Answer:
Immanuel Maurice Wallerstein ( ; September 28 , 1930 – August 31 , 2019 ) was an American sociologist , economic historian and world-systems analyst , arguably best known for his development of the general approach in sociology which led to the emergence of his world-systems approach .


