Imo o omoi i no neraenu ni akatoki no asagirigomori karigane zo naku

妹を思ひ寐の寝らえぬに暁の
朝霧隠り雁がねぞ鳴く

Roma-ji: Imo o omoi i no neraenu ni akatoki no asagirigomori karigane zo naku
English Translation: Thinking of my love
I cannot fall asleep,
and before the dawn,
hidden in the morning mist,
the wild geese are crying
Meaning: Thinking of my wife, I cannot sleep, and in the dark before dawn, hidden in the morning mist, the wild geese are crying.
Commentary: Book Fifteen Poems of the Envoys to Silla 3665

Headnote continued from the preceding poem: "Nine poems composed while gazing at the moon by the sea"
Thinking of his wife, he cannot sleep, and in the dark before dawn the wild geese are crying in the morning mist. The voices of unseen geese convey the loneliness of a sleepless night and the deepening of autumn. Wild geese were held to be birds that carry messages, and in 3676 of this book, made later at Hikitsu Lodge, he wishes he could make a goose his messenger. The first two lines, "imo o omoi i no neraenu ni," are also used in 3678, at the same Hikitsu Lodge.
According to the headnote, this is one of nine poems composed while gazing at the moon by the sea, thought to have been made during the stay at the Tsukushi lodge. The author of this poem is not named.

First line, "imo o omoi": thinking of my wife with longing; a six-syllable hypermetric line.
Second line, "i no neraenu ni": "i" is sleep, "rae" the irrealis of the potential auxiliary "rayu," and "nu" negative: though I cannot sleep.
Third line, "akatoki no": "akatoki" is the dark time before dawn.
Fourth line, "asagirigomori": hidden in the morning mist, so that the geese are unseen and only their voices heard.
Fifth line, "karigane zo naku": "karigane" are wild geese; "zo" is a binding particle resolved by the attributive "naku" (kakarimusubi).
Source: Manyoshu
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