The first phase (from 0 to 9-10 months). - Assimilation of codified impressive speech (verbal and kinetic), of expressive kinetic and uncodified oral expressive speech.
The second phase (from 9-10 months. Up to 11 years) - the assimilation of all forms of codified oral and sign language. This stage, in turn, consists of 4 stages.
the first stage (from 10.9 to 18 months.) – the start in acquisition of language system;
the second stage (from 18 months. Up to 3 years) - the acquisition of "nucleus" of language system;
third stage (from 3 to 5 years) – acquiring the "periphery" of the linguistic system;
the fourth stage (from 5 to 11 years and later) - Improving the existing language system.
The third stage (usually - from 6 to 11 years) - acquisition of written language (reading and writing).
the first stage - acquisition of initial reading skills (from 6 to 8 years old) and letters (from 6-7 to 9 years);
the second stage (from 8-9 to 11 years later) - improving reading and writing skills.
Several theoretical positions have been sketched out here. A complete, consistent, unified theory of first language acquisition cannot yet be claimed; however, child language research has manifested some enormous strides toward that ultimate goal. And even if all the answers are far from evident, maybe we are asking more of the right questions
