started using spoken language several million years ago.]]> people use to communicate, or share information.]]> types of words.]]> came to the Americas hundreds of years ago are one example.]]> borrow words from another language.]]> phones."]]> ideas.]]> ancestors started using spoken language several million years ago.]]> forms of language, however, must be taught.]]> understand language.]]> develop.]]> ability to understand language.]]> devices were first called "cellular phones."]]> blur together.]]> speech.]]>