Final answer:
The phrase 'posture of my father' in 'Height' most likely illustrates a metaphor, where it represents something greater than the literal stance, such as an attitude or life stance.
Step-by-step explanation:
The phrase "posture of my father" in the poem "Height" is a figure of speech that can illustrate several literary devices. However, based on the provided context, it seems likely that this phrase could be an example of a metaphor, where the father’s posture represents something greater, such as an attitude or stance in life that the speaker observes and perhaps aims to emulate or learn from. Another device it may represent is personification, attributing human characteristics to a non-human element if the poem is describing the father's actual physical posture as a sentient expression. It can also demonstrate the use of imagery, evoking visual representation of the father’s stance to the reader. The specific literary device it illustrates may depend on the surrounding context of the phrase within the poem.