if something comes from something else then that something else is a source of that something0 & the sun is the source of solar energy called sunlight ->  plants use solar energy  if a process converts something into something else then that something is used for that process & photosynthesis is a kind of chemical process ->  if photosynthesis converts something into something else then that something is used for that process  if photosynthesis converts something into something else then that something is used for that process & photosynthesis means producers / green plants convert from carbon dioxide and water and solar energy into carbohydrates and food and oxygen for themselves ->  solar energy is used for photosynthesis  plants use solar energy & solar energy is used for photosynthesis & plants perform photosynthesis ->  plants use solar energy to perform photosynthesis  plants use solar energy to perform photosynthesis & green plants provide food for themselves / animals / consumers by performing photosynthesis ->  plants use solar energy to provide food for themselves  plants use solar energy to provide food for themselves & making something is a kind of method for providing that something ->  plants use solar energy to make food  if something comes from something else then that something else is a source of that something & the sun is the source of solar energy called sunlight ->  solar energy comes from the sun  solar energy comes from the sun & solar energy is a kind of energy ->  solar energy is a kind of energy that comes from the sun  plants use solar energy to make food & solar energy is a kind of energy that comes from the sun -> plants use energy from the sun to make food