classic waka stream

千代経れど面変はりせぬ河竹は
流れての世のためしなりけり
Roma-ji

Chiyo furedo omogawari senu kawatake wa nagarete no yo no tameshi narikeri

English Translation
Though a thousand years pass,
never changing its fair face,
the bamboo by the stream
is a model for the ages
flowing on in time to come
Meaning
The river bamboo, whose face does not change though a thousand years pass, is a model for a reign that will flow on into the ages to come.
Commentary
Book Five Celebration Poems 305

Seeing in the river bamboo, unchanged though a thousand years pass, a model for a reign flowing on into ages to come, the poem celebrates the long reign of the sovereign. The unchanging green of the bamboo is likened to a reign that never ends.
This is the opening poem of Book Five, Celebration Poems. Taking up poem 304, which closed Book Four, Winter Poems, with the end of a year, this book begins with something that does not change through a thousand ages. The word tameshi, model, answers 'a model for ten thousand ages' in poem 332 in this book.
From poem 305 through poem 310 in this book come poems celebrating a thousand and ten thousand ages through such things as bamboo, the spring of Iwashimizu, pines, cherry blossoms and the poet's own self.

First line, 'chiyo furedo', means though a thousand years pass, using the concessive do.
Second line, 'omogawari senu', means never changing its appearance, showing the constant green of the bamboo.
Third line, 'kawatake wa', is bamboo growing by a river, also known as the name of the bamboo planted in the east garden of the Seiryōden.
Fourth line, 'nagarete no yo no', means of the ages flowing on, nagare, to flow, being a word related to the river in the third line.
Final line, 'tameshi narikeri', means it is a model, closing with the exclamatory keri. Like the second line of poem 332 in this book, 'seen as a model', it uses the word tameshi.
Source
Kinyo Wakashu
Prev Poem
Nanigoto o matsu to wa nashi ni akekurete kotoshi mo kyō ni narinikeru kana
Next Poem
Yorozuyo wa makasetarubeshi iwashimizu nagaki nagare o kimi ni yosoete