What are the different stages of spoken Child Language Acquisition?

Spoken child language acquisition can be divided into stages which pinpoint the development of a child's language journey; pre-verbal, holophrastic, two-word, telegraphic and post-telegraphic stages. With each stage the child grows older and their spoken language ability becomes more complex. With these stages I have included extra information and knowledge that can help access the highest marks. It is important to note that when trying to pinpoint a child to a stage, they may be in between stages showing identifiable features of both and with that case, it is probably more advanced to write down your observations in your essays as it demonstrates critical thought towards the stages.
Technically speaking a child learns to recognise language before they are even born. Pre-birth, a baby can recognise their mother's voice. Six months before birth ear bones are formed and hearing becomes clearer. A baby is capable of identifying their mother's native language and other languages before birth. However, a child's language journey really does kick-start at the pre-verbal stage post-birth. From when a child is born, the first noise typically made is crying. A child can translate a need (hunger/wind/tiredness) through physical reasoning (crying typically). Not long after 2 months a child begins to experiment making noises with their tongue at the back of their mouth, these noises are notably distinct from crying and are more experimental. A more distinct and repetitive sound is formed at 6 months with a child's babbling, a child will either utilise reduplicated babbling 'bababababa' (repeating the same sounds) or variegated babbling 'dabadabadaba' (alternating either consonant or vowel sounds). During 12-18 months a child will enter the holophrastic stage where one whole sentence worth actual meaning is conveyed using 1 content word called a 'holophrase'. For example, this is the time where a child's first words will occur and typically concrete nouns such as 'mummy' or 'daddy' will be used to define their caregiver (cite: a theorist called Katherine Nelson has done further research into the first words of children).
However, the catalyst to a child's spoken language learning is at the two word stage at 18 months which coincides with what is commonly called the 'vocabulary spurt' or 'naming explosion' where a cognitive change occurs in children and they realise all objects have names. Children adopt a 'naming insight' where they are curious as to what everything is called and will practice the connections between a word and meaning on a daily basis using two words such as 'mummy sit' for example, when their mother does sit then they become aware of the power language has. From this rapid development, at around the age of 2 years old a child will begin experimenting with grammar in the telegraphic stage producing longer and complete utterances. This stage is usually identifiable by nonstandard grammar as the child is still testing the structures of syntax (word order), formations of questions, multiple negation or where a pronoun should sit (cite: a child language theorist Bellugi has published further theories specific to spoken language grammar development in young children). However, in the post-telegraphic stage at age 3 a child will begin to speak increasingly like an adult, by age 4 their spoken language is largely grammatically accurate with complete sentences.