Hnav tsis -} buch thom khwm yog qhov tseem ceeb thaum ua si hauv chaw ua si loj loj loj loj. Ua ntej, cov npoo ntawm cov trampoline feem ntau yog ua los ntawm cov khoom siv pp zoo, thiab cov menyuam yaus nyiam hws thaum ua si. Hws yuav ntxiv cov nyooj slamperiness ntawm trampoline, yog li nce txoj kev pheej hmoo ntawm swb. Thib ob, cov roj hmab tso rau hauv qab ntawm qhov tsis-}} Kev tiv thaiv kev sib txhuam thiab ua kom muaj kev nyab xeeb ntawm cov menyuam yaus thaum ua si. Ib qho ntxiv, txawm hais tias cov chaw ua si tuaj yeem nruab nrog cov kev ntsuas kub ntxhov, tsis muaj kev tiv thaiv cov menyuam yaus kom muaj kev txhawj xeeb txog kev sib npaug lossis slipping. Yog li ntawd, hnav tsis- butter thom khwm yog theem tseem ceeb los xyuas kom muaj kev nyab xeeb chaw ua si.
