Stepping stone
01
飛び石, 渡り石
a stone in a marsh or shallow water that can be stepped on in crossing
02
踏み石, 足がかり
any means of advancement that helps one to make progress towards achieving something
例
The internship served as a stepping stone to her career in marketing.
そのインターンシップは、彼女のマーケティングキャリアへの足がかりとなりました。
