1. Cov thawv noj su, ib puag ncig phooj ywg, tsis muaj tshuaj lom, tsis-swb 2. Quav-pov thawj thiab kaw, lub teeb thiab ke, haum rau siv nyob rau hauv ntau zaus. 3. Stackable los txuag chaw thiab yooj yim los ntxuav