Explain the four rules of language and four stages of language development in children?

The four rules of language are phonology (the sound system), morphology (the structure of Words), syntax (the arrangement of Words in sentences), and semantics (the meaning of Words and sentences). Children typically progress through four stages of language development: the pre-linguistic stage (cooing and babbling), the one-Word stage (using single Words to convey meaning), the two-Word stage (combining two Words to form simple sentences), and the early multi-Word stage (creating more complex sentences with basic grammar). These stages reflect the natural progression from sounds to meaningful communication.