案

1. Origins, structure, and basic meaning

• Structure: It is read あん. This noun names an idea or proposal put forward for consideration or adoption.
• Basic usage: It is used for comparing the costs and timing of proposals or suggesting a new facility.
  • 三つの案を比べて、費用と時間の両面から検討した。

2. Common pitfalls and similar expressions

• A proposal versus an implementation plan
  • 案 emphasizes an idea or option under consideration, while 計画 can describe a plan with methods or steps for implementation.