When I find two sentences which have the same meaning but are expressed in a different way, I take notes because I'm not sure what's the difference between the two. Here is the some of them.
A1. I could release the song.
B1. I could do with releasing the song.
A2. Which is yours?
B2. Which is supposed to be yours?
I don't know those differences.
I'd appreciate if you taught me how different they are.