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one line; one stretch (e.g. of road); one strand (e.g. of hair); one beam (e.g. of light); one ray; one length (e.g. of rope)
earnest; resolute; intent; devoted; single-minded
遠くの山から一すじの煙が立ち上っていた。
A single plume of smoke was rising from a distant mountain.
一すじの川が平野を横切って海に注いでいる。
A single river crosses the plains and flows into the sea.
彼女の頬に一すじの涙が伝い落ちた。
A single tear rolled down her cheek.