Ua ntej, xaiv cov khoom ua si uas tsim nyog rau hnub nyoog. Raws li tus menyuam hnub nyoog, xaiv cov khoom ua si uas haum rau lawv kom tsis txhob muaj cov khoom ua si uas ua rau tsis xis nyob lossis raug mob rau tus menyuam lub cev. Piv txwv li, cov cuab yeej nce toj nrog cov qauv steel yog tsim rau cov menyuam yaus hnub nyoog qis dua 6 xyoo, thaum cov khoom siv tumbling yog tsim rau cov menyuam yaus hnub nyoog qis dua 4 xyoos.
Thib ob, xaiv cov cuab yeej kev lom zem uas muaj kev nyab xeeb thiab txhim khu kev qha. Thaum xaiv cov cuab yeej kev lom zem, nws yuav tsum tau ua tib zoo saib xyuas seb cov khoom siv kev lom zem ua tau raws li cov qauv kev nyab xeeb hauv lub tebchaws thiab cov kev cai lij choj thiab cov kev cai, thiab seb puas muaj kev tiv thaiv kev nyab xeeb, xws li lub rooj zaum, guardrails, thiab lwm yam. Tib lub sijhawm, nws tseem yuav tsum tau xav txog qhov ua tau ntev thiab zoo ntawm cov cuab yeej lom zem.
Thib peb, xaiv cov khoom siv lom zem lom zem. Txhawm rau kom cov menyuam nyiam thiab ua kom muaj kev lom zem, cov cuab yeej ua si yuav tsum muaj kev lom zem thiab muaj tswv yim. Piv txwv li, swb, viav vias, kev sib hloov thiab lwm yam khoom siv ua si yog txhua yam uas cov menyuam nyiam.
Plaub, xaiv cov cuab yeej lom zem uas haum rau qhov chaw. Raws li qhov loj thiab cov duab ntawm qhov chaw ua si sab nraum zoov, xaiv cov khoom siv lom zem uas tsim nyog. Feem ntau, cov khoom siv lom zem loj yog tsim rau cov chaw loj, thaum cov khoom siv lom zem me me yog tsim rau cov chaw me me.
Thib tsib, xaiv cov khoom muaj npe nrov. Thaum xaiv cov khoom siv kev lom zem, koj yuav tsum xaiv cov chaw tsim khoom tsim nyog thiab muaj npe nrov, koj tuaj yeem xa mus rau kev xaiv ntawm lwm qhov chaw kom nkag siab txog tus neeg muag khoom cov txheej txheem tsim khoom, kev pab cuam tom qab muag thiab lwm yam.
