The process of child language acquisition and adult language acquisition

Language acquisition is the process where the child acquired the language, in this term, The process of acquiring language between the child and the adult has some similarities and differences.
The similarities in the acquisition process between child and adult is on the language production which show the development of syntax and morphological of the language, it is in line with Harley (1986) cited in Takayki (2015) who suggests that children and older learners has similarity in the development of the syntax and morphology of the L2 that include common language acquisition processes, the rules of language and how to use the language in the communication. In this case, Schwartz (2003) cited in Al-Kafri (2009) point out that similarity between child and adult in language acquisition lay in realm of inflectional morphology. In addition, the developmental sequential of both child and adult in acquiring language is also similar, in this term, Ellis (1984) covers the idea of developmental sequences in detail and outline three developmental stages; the silent period, formulaic speech and structural semantic simplification. In this term, both child and adult immersed in the new learning, and it is a basic thing to acquire language among children and adults, they acquire language through the stages of developmental sequences of language and they like to know a new thing as a process of knowledge.
Another similarity is seen from the risk-free environment that can support for the language acquisition of child and adult to make a warm and relaxed environment that encourages them to speak and improve the language. a child and adult learner has good responses to the language where they get good stimulus from surrounding, and it can utilize them to acquire language better, it is in line with the behavioristic approach that language acquisition is environmentally determined, and the environment provides the language learner with language, which acts as a stimulus, to which the language learner responds. However, a child and adults can form and repeat sentences from the words that they have and heard and these habits interfere with those needed to new habits of language (Lightbown & Spada, 2006).
On the other hand, there also differences between child and adult in acquiring language that include age and types of learning. Age is one thing that shows difference in language acquisition for child and adult, a child with golden age can acquire language easily through his environment and it is in line with the ideas of the psychologist Eric Lenneberg (1967) cited in McLaughlin, (1987) that various capacities mature according to a fairly fixed schedule during which language emerges in children when anatomical, physiological, motor, neural, and cognitive development allow it to emerge. He added that there is a critical, biologically determined period of language acquisition between the ages of 2 and 12 (p. 145). Another one is types of learning. The child acquires language subconsciously, through informal and implicit learning. He/she acquire the language by imitation and repetition. On the contrary adult acquire language through the classroom activity and it is consciously done to know about language with explicit and formal linguistic knowledge