1. Muaj ntau qhov seem ntawm cov khoom
Yog vim li cas: Cov residue feem ntau yog los ntawm qhov nruab nrab kom qhuav, cov khoom ua kua thiab cov khoom siv ziab.
Kev daws: Txheeb xyuas cov lim cua, thiab hloov cov ntxaij lim dej kom zoo uas tau siv rau lub sijhawm ntev; coj cov qauv ntawm cov kua pub thiab lim cov seem; ntxuav cov cuab yeej kom huv si.
2. Phab ntsa nplaum tshwm sim
Yog vim li cas: cov khoom noj ceev ceev heev thiab cov nyiaj ntau dhau, ua rau kom qhuav tsis tiav; cov khoom siv tsis ua haujlwm raws li qhov yuav tsum tau ua, thiab lub ntsiab ntauwd ntawm cov khoom siv tsis tau rhuab.
Kev daws: txo qhov ceev ceev thiab kom muaj nuj nqis, kho lub twj tso kua mis noj kom tsim nyog; nce qhov nkag thiab qhov hluav taws xob kub; saib seb puas muaj cov khoom thaiv hauv cov khoom siv;
