Standard mankhwala mitu: kupanga sikani mutu ndi opaleshoni mutu;Pazovuta zosiyanasiyana zapakhungu: kuchotsa ma tag a pakhungu, kubwezeretsanso khungu, kuchepetsa mabala, kuchotsa mawanga, kuchotsedwa kwa mabala, kuchotsa zipsera ndi ziphuphu, etc.;