Clarify: to make understandable; to make free of confusion
澄清
Elaborate: to expand something in detail (ornateness, complexity)
詳盡說明 / 細節
Elucidate: to give a clarifying explanation through analysis
透過分析 闡明,說明
Could you please clarify your plan
(I’m confused, make it simple)
Could you please elaborate on your plan
(I get it, I want more details on how it works)
Could you please elucidate on your plan
(I want to know the data on how you got to this conclusion)