Hurry! says the father,
Time to go to bed!
Slowly, says the darkness,
You can talk to me...
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It is from a poem.
Q1: Why do we have to put 'the' before 'father' and 'darkness'?
Q2: Can't we say as follows?
Hurry! the father says,
Time to go to bed!
Slowly, the darkness says,
You can talk to me...
If you change the words around so they're not the same as in the poem, the meaning stays the same, but the lines don't have the same rhythm.
In English, a poem's rhythm is made by how the poet arranges the stressed and unstressed syllables. Here's now the poem's lines sound (capitalized syllables are stressed, that is, spoken a bit more loudly than the others).
HUR ry! says the FA ther,
TIME to GO to BED!
How can you demonstrate this with the other stanza from the poem -- and with the two stanzas in which the words are moved around?
Here are some websites that explain rhythm and meter in English poetry:
https://www.writing.upenn.edu/~afilreis/88/meter.html
and
https://literarydevices.net/rhythm/
and
https://www.poetry4kids.com/lessons/rhythm-in-poetry-i-am-the-iamb/