"
And mom in her kerchief
And I in my cap,
Had just settled down
For a long winters nap
When out on the lawn
There arose such a clatter
I sprang from my bed
To see what was the matter
Away to the window
I flew like a flash
Tore open the shutters
And threw up the sash
The moon on the breast
Of the new fallen snow
Gave the lustre
Of midday
To object below
They had just got ready to go to bed, and were totally not prepared. Then there was a loud noise on the yard, and the author jumped up to make sure there were no burglars/no one was hurt/there wasn't an accident. He rushed to the window because he was worried or scared. The last part describes how the light was shining. It's very descriptive.

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