"あの星があなたで" and "あの星はあなただ", between those two, what's the difference?


Both have the same meaning: "That star is you." But what makes them different?
If it's the nuance, what exactly is it?

Context: It's from a song's lyrics, the first one get sang first, whilst the
latter get sang later.




だ is the basic form of the copula, so あの星はあなただ is a complete sentence.

で is the continuative form of だ, so あの星はあなたで is not a complete sentence; it
leads into whatever follows.

Basically あの星はあなただ is simply "That star is you", whereas あの星はあなたで is more like
"That star is you, and..."

