✔ 最佳答案
The introduction of the Earth:
Up to the present for this reason, the Earth has the biological staronly. It is the solar system third planet, is also in the solar systemcrag nature star biggest one.Earth's special place has bred the life, and contains the oxygen richlyincluding the massive liquid waters. The earth's surface 70% above areaare the water, but the atmospheric constituent also has the finecondition breeding life, moreover atmosphere thickness may endure theouter space small meteorite the hit. Moreover the Earth and sun'sdistance is moderate, can not evaporate the moisture content by thesolar thermal energy or the temperature excessively low commandmajority of water does not send in ices up.