What are the phases of child's acquisition of language?

babbling phase (babies make sounds)

cv (consonant - vowel reduplications) e.g. ga ga ma ma

one-word phase - children may point to something and say the word, one word suffices for a whole sentence e.g. 'that' for "I want that one"

two-word phase - two words suffice for a whole sentence e.g. 'that one' or 'ball table' for 'the ball is on the table'.

Here children don't have a very big vocabulary so they over-extend the meaning e.g. 'cat' for anything furry with 4 legs or 'car' for any vehicle.

three-word phase - more likely to use small grammatical words but may still get words in the wrong order e.g. 'want that one' or 'that one spoon'

From here on children continue to develop vocabulary (about age 2.5-3 years) and are able to speak in mainly full sentences, gaining hundreds of new words each month. Meaning narrows as they learn more words.

At each phase it is important to talk to the child and 'answer' them when they make noises so that they develop turn-taking in conversation.