(Please see Corrections & Amplifications below.) Do the languages we speak shape the way we think? Do they merely express thoughts, or do the structures in languages (without our knowledge or consent) shape the very thoughts we wish to express? Take "Humpty Dumpty sat on a..."

People have always spoken differently from how they write, and texting is actually talking with your fingers Texting has long been bemoaned as the downfall of the written word, "penmanship for illiterates," as one critic called it. To which the proper response is LOL.

English will still dominate a century from now, but it will no longer share the planet with thousands of other languages. Instead, expect fewer but simpler modes of oral communication on every continent.

Jack Hitt article on how languages die and efforts to keep them alive; notes estimate that half of more than 6,000 languages currently spoken in world will become extinct by end of century; says working to stem tide range are graduate students heading into the field to compile dictionaries, charitable foundations devoted to the cause, like Endangered Language Fund, and transnational agencies, like European Bureau for Lesser Used Languages; describes scene in Puerto Eden, tiny fishing village on Wellington Island in Patagonia region of southern Chile, home of last six speakers of Kawesqar, language native to area since last ice age; photos (L)