primary reason 意味

• 一番の理由、主な理由｛りゆう｝、一義的｛いちぎてき｝な理由｛りゆう｝
  

例文

1. but perhaps the primary reason
   でも 恐らく一番の要因は
2. the primary reason you were never able to build a case against pendry was that you could not find the murder weapon .
   君が ペンドリーに対する容疑を 事件化できなかった第一の理由は 君が凶器を発見できなかったからだ
3. some have argued that the primary reason for takeda ' s crushing defeat was the employment of traditional tactics for field battle and cavalry charge .
   従来通りの野戦と騎馬隊突撃の戦術を用いたのが大敗の一番の理由とする説もある。