Zach

Zach uses substitution when he uses the utterance "it doesn't go frough" he does this by replacing the phoneme 'th' with the simpliar phoneme 'f'. There is a possible reason for this regarding his accent; where his social group ,e.g nursery friends, uses an accent which involves non-standard English, influencing Zach's to speak this way. Some social groups, if this is the case, do pronounce the lexical choice 'three' by changing it to the Simpliar phoneme 'free', and in this instance could be the reason for this, however, immediately after Zach says this , his care giver, Halla repeats the utterance, correcting Zach using standard English subconsciously. From this we know that Zach's care givers do not use non-standard English within their accent which could which potentially be the reason for why Zach uses simplification by substitution instead depending on ho much time he spends with his care givers in addition to how much time he spends with his nursery friends- which he is very unlikely to see his nursery friends more than his care givers.
 In addition to this, we can also get a greater idea of how might he learn new phonemes from his care givers; by Halla modeling subconsciously shows how much he will learn new new language by being exposed to subconscious modeling which will encourage him to move out of the telegraphic stage and onto the post-telegraphic stage.

on the other hand this could also be opposed to his nursery friends if they did use non-standard English often when interacting in conversation with them- this may confused Zach