Yeyiphi into enokutshiswa iziko lomlilo?

Izinto ezinokutsha ezithiyori azibandakanyi kuphela umgubo oqinileyo, kodwa kunye ne-liquid okanye i-semi-solid, kodwa ekusebenzeni ngokwenene, qaphela ukhuseleko. Ukutshisa igesi enobungozi okanye izinto eziqhumayo kufuneka zenziwe ngokuhambelana nemimiselo yokusebenza kunye nemigangatho.