Furbies start out speaking entirely `` Furbish '' , a language with short words , simple syllables , and various other sounds . They are programmed , however , to speak less and less Furbish and more and more English as they `` grow '' .
A newly bought Furby starts out speaking entirely Furbish , the unique language with short words , simple syllables , and various other sounds , that all Furbies use , but are programmed to speak less Furbish as they learn more English as they `` grow '' .