主要原因primary reason

• 国民阵线推行的种族和谐和发展经济政策是使它立于不败之地的主因。

  The Barisan National's promotion of ethnic harmony and its policies for economic development are the primary reasons it attained an unbeatable position.

• 后天因素是诱发癌症的主因。

  Acquired factors are the main reasons for the onset of cancer.