• 提案ていあん — proposal / suggestion
• 案内あんない — guidance / showing around
• 案件あんけん — matter / agenda item
• 考案こうあん — idea / invention
• 案文あんぶん — draft text
• 案外あんがい — unexpectedly

The kanji 案 combines 宀 (roof) with 安 (peace) to suggest the idea of thinking peacefully under a roof — reflecting the act of pondering or planning. It originally referred to a physical desk or table, and later extended to ideas, plans, and proposals made at such places.

新あたらしい案あんを出だしました。
I presented a new proposal.

彼かれの案あんは とてもいいと思おもいます。
I think his idea is really good.

案内あんないしていただけますか？
Could you show me around?