Kaku bakari ame no furaku ni hototogisu unohanayama ni nao ka nakuramu

かくばかり雨の降らくに霍公鳥
卯の花山になほか鳴くらむ

Roma-ji: Kaku bakari ame no furaku ni hototogisu unohanayama ni nao ka nakuramu
English Translation: Though so heavily
all this while the rain comes down,
hototogisu,
on the hills of unohana,
are you singing even still?
Meaning: Though the rain falls so heavily, is the hototogisu still singing on the hills where the deutzia blooms?
Commentary: Book Ten Summer Miscellaneous Poems 1963

Headnote continued from the preceding poem: "On Birds"
This poem wonders whether, even in such heavy rain, the hototogisu is still singing on the hills where the deutzia blooms, and it closes the bird group of the summer miscellaneous poems. It shows the heart of a poet shut in by the rain, longing for the voice of a bird on distant hills. It sings the pairing of deutzia and hototogisu, seen in 1953 and elsewhere, as an imagined scene in the rain.

The first line, "kaku bakari," means this much.
In the second line, "ame no furaku ni," "furaku" is the nominalized form of "furu" and "ni" is adversative: though it rains so.
The third line, "hototogisu," is the subject.
The fourth line, "on the deutzia hills," names where the bird may be.
In the last line, "nao ka nakuramu," "ka" is an interrogative particle in kakari-musubi with the attributive "ramu," closing by imagining the present scene on the distant hills.
Source: Manyoshu
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