What is this whole saying?

[Sister Girl]

nothing can bring back the splendor in the grass.

[Quizmonster]

"Though nothing can bring back the hour
Of splendour in the grass,
of glory in the flower,
We will grieve not, rather find
Strength in what remains behind."

The above are the key lines of the Wordsworth poem.

[Quizmonster]

Click here here for the whole poem. See particularly Part X lines 10 -13.