Tsis muaj
Tshem tawm cov yeeb yaj kiab tiv thaiv maus taus feem ntau tsis ua mob rau cov xim. Qhov no yog vim tias cov yeeb yaj kiab tiv thaiv zoo yog tsim los kom tshem tau yooj yim thiab yuav tsis tawm cov kua nplaum los yog lwm yam khoom seem uas yuav ua rau cov xim puas. Thaum lub sij hawm siv zaj duab xis thiab txheej txheem tshem tawm, tsuav yog siv cov txheej txheem thiab cov ntaub ntawv tsim nyog, cov xim qub tuaj yeem tiv thaiv kev puas tsuaj. 12
Tsis tas li ntawd, qee cov neeg siv kev paub kuj qhia tau hais tias txawm tias cov maus taus zoo tib yam yuav tsis ua rau lub tsheb puas tsuaj thaum cov yeeb yaj kiab tiv thaiv raug tshem tawm thiab ntsia, vim tias cov xim ntawm cov maus taus niaj hnub no kuj tawv thiab tuaj yeem tiv taus kev sib txhuam thaum lub sijhawm ua haujlwm. Yog li ntawd, txoj kev tshem tawm cov yeeb yaj kiab kom raug thiab cov txheej txheem yog qhov tseem ceeb ntawm kev ua kom muaj kev nyab xeeb ntawm cov xim pleev xim.