what do you mean by the first one?
It is a gestural communication system, often invented spontaneously by a deaf child who lacks accessible linguistic input.
Home sign
Home sign (or kitchen sign) is a gestural communication system, often invented spontaneously by a deaf child who lacks accessible linguistic input.
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 when did the sign language develop? Fifth Century BC what is its relationship with spoken language? They  are independent of spoken languages and follow their own paths of development how are they classified? Home sign, pidgin, creolization
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Home sign [SEP] Introduction
Home sign (or kitchen sign) is a gestural communication system, often invented spontaneously by a deaf child who lacks accessible linguistic input. Home sign systems often arise in families where a deaf child is raised by hearing parents and is isolated from the Deaf community. Because the deaf child does not receive signed or spoken language input, these children are referred to as linguistic isolates. Because home sign systems are used regularly as the child's form of communication, they develop to become more complex than simple gestures. Though not considered to be a complete language, these systems may be classified as linguistic phenomena that show similar characteristics to signed and spoken language.