▁published ▁several ▁collections ▁of ▁papers ▁on ▁the ▁G be ▁languages . ▁ ▁In ▁the ▁early ▁ 1 9 9 0 s , ▁S IL ▁International ▁initi ated ▁a ▁study ▁to ▁assess ▁which ▁G be ▁communities ▁could ▁benefit ▁from ▁existing ▁liter acy ▁efforts ▁and ▁whether ▁additional ▁liter acy ▁campaign s ▁in ▁some ▁of ▁the ▁remaining ▁communities ▁would ▁be ▁needed . ▁S ynchron ised ▁lingu istic ▁research ▁carried ▁out ▁in ▁the ▁course ▁of ▁this ▁study ▁shed ▁more ▁light ▁on ▁the ▁relations ▁between ▁the ▁various ▁vari eties ▁of ▁G be . ▁In ▁general , ▁the ▁S IL ▁studies ▁cor ro bor ated ▁many ▁of ▁Cap o ' s ▁find ings ▁and ▁led ▁to ▁adjust ment ▁of ▁some ▁of ▁his ▁more ▁tent ative ▁group ings . ▁ ▁Ph on ology ▁ ▁Cons on ants ▁The ▁following ▁ph on etic ▁segments ▁are ▁att ested ▁in ▁G be ▁languages : ▁ ▁Notes ▁The ▁ap ico - post al ve olar ▁con son ants ▁are ▁generally ▁written ▁and ▁trans cribed ▁with ▁the ▁symbols ▁for ▁the ▁corresponding ▁al ve olar ▁con son ants , ▁except ▁for ▁the ▁vo iced ▁stop , ▁which ▁uses ▁the ▁symbol ▁for ▁the ▁vo iced ▁retro flex ▁stop ▁. ▁This ▁is ▁only ▁to ▁distinguish ▁it ▁from ▁the ▁l am ino - d ental ▁vo iced ▁stop , ▁and ▁is ▁not ▁to ▁be ▁interpreted ▁as ▁the ▁con son ant ▁being ▁sub ap ical . ▁The ▁above ▁table ▁lists ▁the ▁att ested ▁ph on etic ▁segments . ▁Some ▁of ▁the ▁sounds ▁listed ▁here ▁are ▁in ▁free ▁variation ▁with ▁other