green plants are a kind of producer & green plants provide food for themselves / animals / consumers by performing photosynthesis ->  producers provide food for themselves by performing photosynthesis  producers provide food for themselves by performing photosynthesis & making something is a kind of method for providing something ->  producers make food by performing photosynthesis  photosynthesis is a kind of chemical process & if a process converts something into something else then that something has the role of raw material in the process ->  if the photosynthesis process converts something into something else then that something has the role of raw material in the photosynthesis process  if the photosynthesis process converts something into something else then that something has the role of raw material in the photosynthesis process & photosynthesis means producers / green plants convert from carbon dioxide and water and solar energy into carbohydrates and food and oxygen for themselves ->  in the photosynthesis process carbon dioxide / water / sunlight has the role of raw material  in the photosynthesis process carbon dioxide / water / sunlight has the role of raw material & if something is a raw material in a process then that something is required for that process ->  sunlight and water and carbon dioxide are required for the photosynthesis process  producers make food by performing photosynthesis & sunlight and water and carbon dioxide are required for the photosynthesis process ->  producers require sunlight and water and carbon dioxide to make food  producers require sunlight and water and carbon dioxide to make food & to require something means to need something -> producers need sunlight and water and carbon dioxide to make food