I-valve iyithuluzi noma into engokwemvelo elawula, eqondisa noma elawula ukugeleza koketshezi (amagesi, uketshezi, okuqinile okuketshezi, noma ama-slurries) ngokuvula, ukuvala, noma ukuvimbela kancane amaphaseji ahlukahlukene. Amavalvu ayizinto zokufakelwa ngokobuchwepheshe, kodwa ngokuvamile axoxwa njengesigaba esihlukile. Esikhathini...
Funda kabanzi