Looking up at the moon, what sank back, I suddenly remembered the last sentence of home?

"Looking up, I found it was moonlight, and when I sank back again, I suddenly thought of home" means:

I couldn't help looking up at the bright moon in the sky outside the window that day, and I couldn't help but bow my head and think of my hometown in the distance.

The original sentence is from the Tang Dynasty poet Li Bai's Thoughts on a Quiet Night, and the original text is as follows:

The foot of my bed is shining so brightly. Is there frost already?

I looked up at the moon and looked down, feeling nostalgic.

Translation:

The bright moonlight sprinkled on enough paper in front of the bed, as if the ground was frosted.

I couldn't help looking up at the bright moon in the sky outside the window that day, and I couldn't help but bow my head and think of my hometown in the distance.

This poem is about the feeling of missing my hometown on a silent moonlit night.

The first two sentences of the poem are an illusion created by the poet in a specific foreign environment in an instant.

A person living alone in a foreign country, busy during the day, can also dilute his sadness, but in the dead of night, his heart will inevitably be submerged.

There are waves of homesickness. Not to mention on a moonlit night, not to mention on a frosty autumn night.

On the other hand, the last two sentences of the poem deepen homesickness through the description of actions and ways.