Which sound devices are used in line 1 of the poem?

There are many types of sound devices. For example,

Assonance: Assonance is the repetition of vowel sounds in the same line.
Consonance: Consonance is the repetition of consonant sounds in the same line.
Alliteration: Alliteration is the repetition of consonant sounds in the same line.
Meter: It is a unit of rhythm in poetry, the pattern of the beats.
Onomatopoeia: It refers to the word which imitates the natural sounds of the things.

To create unity throughout the poem

A. an is indefinite article