In contrast, the supply of fossil sources of energy such as oil, natural gas or coal becomes less and less as these energy sources are used.
(the supply of fossil sources of energy such as oil, natural gas or coal; becomes; less and less as these energy sources are used) (these energy sources; are used; )
the supply of fossil sources of energy such as oil, natural gas or coal these energy sources
becomes are used
less and less as these energy sources are used