Answer:
1 - ballad - a poem that tells a story, and is often intended to be sung
2 - cadence = rhythm that regularly repeats itself
3 - poetic diction - the language or word choice of a poet
4 - doggerel - poetry that is not artistic in form or meaning; crude or poor poetry
Explanations
1. Ballad: A ballad is a verse form that tells a story in its stanzas. A characteristic feature of ballads are that they are set to music - more or less recited in the manner a song would be. The rhyme structure basically includes the arrangement of the verses in quatrains (ABAB).
2. Cadence: Cadence is essentially the flow of the poetry, how it unfolds in terms of its musical elements. It can be accurately described as the rhythmic rise and fall of the intonation of voice, or the tone of the poem. For example, a comma or full stop or dash in the poem may demand a pause to follow. Cadence may even change verse to verse, or may be particular to certain parts of the poem -such as the ending note of every stanza or the beginning of every stanza.
3. Poetic Diction: Poetic diction refers to the language of the poem, the metaphors, the vocabulary and may also include any allusive verses, personifications (the linguistic manner of the poem). Poetic diction was strictly adhered to before the 1800s, with the poets making use of figurative language and vocabulary that was of a higher scale than that of the common man's. The strictness to adhere to this protocol has diminished over the year's following Wordsworth's notion that poetry must be understandable to the common man fairly easy for it to impact him.
4. Doggerel: Doggerel is a form of poetry that has an unusual rhyme scheme which comes off unrefined and novice. The construction of this form of poetry is termed to be very poor, with their being irregular meters and a lack of eloquence in the poem. This is why doggerels are mostly employed to describe an occurence with humor, or comically.
Hope this helps!