核かく心しん的てき

na-adjective

crucial; critical; vital; core

Describes the most important, central, or essential part of something. Often used in formal or analytical contexts.

• この問もん題だいの核かく心しん的てきな部ぶ分ぶんを理り解かいする必ひつ要ようがある。

  We need to understand the crucial part of this problem.