Iso no ma yu tagitsu yamagawa taezu araba mata mo aimimu aki katamakete

磯の間ゆたぎつ山川絶えずあらば
またも相見む秋かたまけて

Roma-ji: Iso no ma yu tagitsu yamagawa taezu araba mata mo aimimu aki katamakete
English Translation: Through the rocky shore
the mountain stream tumbles down;
if, like it, I last
I will see this place again
when autumn comes round
Meaning: Like the mountain stream tumbling through the rocks of the shore, if I endure unbroken, I shall come and see this place again when autumn comes.
Commentary: Book Fifteen Poems of the Envoys to Silla 3619

Headnote continued from the preceding poem: "Five poems composed while anchored by the rocky shore of Nagato Island in Aki Province"
As the mountain stream tumbling between the rocks of the shore never ceases, so, if he remains safe, he will see this place again on the way home in autumn. Into the river's unbroken flow he weaves his wish for a safe journey. Returning in autumn was also the promise made to his wife at departure, and the autumn reunions promised in 3581 and 3586 of this book are repeated here as a promise to see the land again.
According to the headnote, this is one of five poems composed while anchored by the rocky shore of Nagato Island in Aki Province, thought to be present-day Kurahashi Island in Kure, Hiroshima Prefecture. Of the five, only the first has its author named in a left note; the author of this poem is not named.

First line, "iso no ma yu": "yu" marks passage: through the gaps between the rocks of the shore.
Second line, "tagitsu yamagawa": "tagitsu" means water rushing violently: the mountain stream tumbling between the rocks.
Third line, "taezu araba": implying "as the stream never ceases," it supposes: if I too continue unbroken and safe. The lines up to here form a simile.
Fourth line, "mata mo aimimu": "mu" is an auxiliary of intention: I will see this place again.
Fifth line, "aki katamakete": "katamaku" means to await a season, for that time to arrive: when autumn comes. It is inverted with the fourth line.
Source: Manyoshu
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