when did the sign language develop?
Fifth Century BC
Sign language
Groups of deaf people have used sign languages throughout history. One of the earliest written records of a sign language is from the fifth century BC,
ways in which infants learn the meanings of new words Infants must be able to hear and play with sounds in their environment, and to break up various phonetic units to discover words and their related meanings. at what age do they start speaking? At one year how do they develop their oral languages? Perception of speech, observe the mouth movements of others , discriminate sound phonologically what will be their first choice of words? "No" and "dada" when does babbling occur? It begins between five and seven months of age what is manual babbling? It is when infants babble with their hands and grow up using sign language how does this occur in deaf infants? Manual babbles are characterized by repetitive movements that are confined to a limited area in front of the body similar to the sign-phonetic space used in sign languages what is vocabulary spurt? UNANSWERABLE
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Sign language [SEP] History
Groups of deaf people have used sign languages throughout history. One of the earliest written records of a sign language is from the fifth century BC, in Plato's "Cratylus", where Socrates says: "If we hadn't a voice or a tongue, and wanted to express things to one another, wouldn't we try to make signs by moving our hands, head, and the rest of our body, just as dumb people do at present?" Until the 19th century, most of what is known about historical sign languages is limited to the manual alphabets (fingerspelling systems) that were invented to facilitate transfer of words from a spoken language to a sign language, rather than documentation of the language itself.