忠诚这个概念对他来说是完全陌生的。

The concept of loyalty is completely ___be ___foreign ___to him.

如此粗俗的行为与他温和的本性格格不入。

Such vulgarity was ___be ___foreign ___to his gentle nature.

工程师们使用的技术术语对市场团队来说难以理解。

The technical jargon used by the engineers was ___be ___foreign ___to the marketing team.