Grammatical jargon Lojban brivla bridi gadri gismu cmavo rafsi lujvo fu'ivla cmene selma'o tanru sumti selbri English attitudinal veridical audio-visual isomorphism Lojban culture Lojbanistan Lojban Central The Book malglico LLG JL LK baseline Tengwar Lojban (pre)history TLI JCB Loglan