Ntuj Hloov 5 yam teeb meem ntawm txhua yam nyob ib puag ncig uas peb yuav tsum xav txog (5 environmental problems) 5 yam teeb meem ntawm txhua yam nyob ib puag ncig uas peb yuav tsum xav txog. (5 environmental problems we to consider) 5 yam teeb meem no yog 5 yam uas ua teeb meem rau lub ntiaj teb zim txwv no, yog
