to carry through; to achieve; to see something through to the end
一度決めたことは必ず遣り通すと彼は言った。
He said he would definitely see through whatever he decided to do.
困難があっても計画を遣り通す覚悟が必要だ。
You need the resolve to carry the plan through even when difficulties arise.
彼らは最後まで遣り通して、プロジェクトを成功させた。
They saw it through to the end and made the project a success.