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parallel lines
remaining far apart (e.g. in discussions); not reaching an agreement
定規で平行線を引いた。
I drew parallel lines with a ruler.
議論は平行線のままだ。
The discussion remains at a standstill, like parallel lines.
彼らの意見はまるで平行線のように、決して交わることはない。
Their opinions are like parallel lines; they will never intersect.