fill in the gaps with the correct preposition.They,correct the statements.Compare with your partner. 1.LifeEarth arose in an oxygen-rich environment.
2.Our bodies process oxygen 100% effectiveness
3.Oxygen has always been present the atmosphere.
4.The appearance of photosynthesis plant is known as the Great Oxidation Event.
5.Evidence suggests animal life appeared
land and the oceans about the same time.
6. Land animals depend land plants for most of their oxygen

aluanakim    3   29.01.2021 16:23    23