Nta:1. yooj yim rau nruab thiab yooj yim;
2., muaj zog fixation, zoo tag nrho stability;
3. xim yas txheej muaj corrosion kuj zoo thiab zoo nkauj nyhuv;
4. fencing network tsos, xim xaiv: ntsuab, xiav, liab, daj, dawb, dub.
Sau koj cov lus ntawm no thiab xa tuaj rau peb
Cov khoom pom zoo