Which poetic techniques are illustrated in the opening lines “i am fourteen/and my skin has betrayed me/the boy i cannot live without/still sucks his thumb/in secret”?
alliteration and metaphor
allusion and alliteration
apostrophe and simile
personification and enjambment

Personification and Enjambment.

The line "and my skin has betrayed me" implies that his skin has literally committed an act of treachery against him, which is something only a human can do; a human quality.

Each of the lines are actually a continuation of a sentence, and only come to a full stop until the end, thus enjambment was used here.

C.they are verbs.