Khoom nta:
1. Cov khoom siv ABS, me nyuam mos tom dawb, ABS khoom, tus me nyuam tsis txhawj txog kev noj tom.
2. Cov hniav ntawm tus khej yuav hloov nrog txhua qhov kev ua si.
3. Me me thiab zoo heev, nqa tau yooj yim, nrog ib txoj hlua qhov ntawm tus Tsov tus tw, uas tuaj yeem nqa mus ncig.
4. Cov tsos yog du, puag ncig thiab angular, tiv thaiv tus me nyuam ob txhais tes.