- 问题详情:Spaceisadangerousplace,notonlybecauseofmeteors(流星)butalsobecauseofraysfromthesunandotherstars.Theatmosphereagainactsasourprotectiveblanketonearth.Lightgetsthrough,andthisisnecessaryforplantstomakethefoodthatweeat.Heat,too,makesourenvironmen...
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