Much of the oxygen produced during photosynthesis is used up during respiration by animals, decomposers and the plants themselves to yield carbon dioxide and water once more.
(the oxygen; produced; T:during photosynthesis) (Much of the oxygen; is used up; T:during respiration by animals, decomposers and the plants)
the oxygen Much of the oxygen
produced is used up
T:during photosynthesis
T:during respiration by animals, decomposers and the plants