Monga kutsegula, kutseka ndi kulamulira chipangizo cha mpweya wabwino ndi fumbi kuchotsa payipi, mpweya wagulugufe valavu ndi oyenera mpweya wabwino, kuchotsa fumbi ndi machitidwe chitetezo chilengedwe mu zitsulo, migodi, simenti, makampani mankhwala ndi mphamvu.Gulugufe wa mpweya wabwino v...
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