. Hauv tsab xov xwm no kuv hais txog Wanger cov tswv yim xaiv cov khoom lag luam thiab muab koj cov npe ntawm cov khoom lag luam tam sim no dhau peb lub vijtsam raws li txoj hauv kev. Ralph Wanger txoj kev nqis peev ntawm kev tuav cov tuam txhab me ...