Cov rooj tua hluav taws tsuas yog qhib tau sab laug yog tias lawv tau qhib txoj kev cai lij choj, xws li nrog lub qhov rooj qhib dawb.
Nws yog qhov txaus ntshai rau 'prop' lossis 'wedge' qhib lub qhov rooj hluav taws. Cov rooj hluav taws kub tau haum nrog tus kheej kaw cov cuab yeej kom yog tias lub cub tawg tawm, lawv kaw thiab yuav ua raws li npaj siab. Yog tias lub qhov rooj hluav taws yog qhov qhib qhib, nws yuav tsis qeeb lossis nres qhov kis hluav taws. Siv lub qhov rooj hluav taws xob ceev los yog lub qhov rooj dawb ceev dua yuav ua rau muaj hluav taws qhov rooj hluav taws yuav tseem nyob ze, txhawm rau kev nyab xeeb kom ruaj ntseg.
Cov rooj tua hluav taws tuaj yeem ua hnyav thiab ua haujlwm ua haujlwm. Lawv kuj tseem tuaj yeem ua teeb meem kev nkag hauv qee lub tsev. Lub qhov rooj hluav taws xob khaws cia, xws li Dorgard, yog cov kev daws teeb meem thiab kev cai lij choj rau cov teeb meem no. A delorgard hluav taws rooj siv tau yooj yim tau haum rau lub qhov rooj hluav taws uas twb muaj lawm thiab yuav hnov lub qhov rooj hluav taws kom txog thaum nws hnov 'lub suab ntawm koj lub tswb hluav taws. Thaum lub tswb nrov, Dorgard yuav tso lub qhov rooj hluav taws, tso cai rau nws kom kaw, tsum tsis txhob tua hluav taws. Lub qhov rooj hluav taws xob khaws cia tseem tuaj yeem pab txhim kho kev nyab xeeb ntawm qhov cua.
